On what date will the benchmark UK 30-year gilt yield first close at or outside the range 5.35%–5.72%?

• My median prediction for the benchmark UK 30-year gilt yield to first close outside the 5.35%–5.72% range is 30th July 2026.
• The yield is currently trading near 5.54%, leaving a narrow margin of approximately 18–19 basis points before a range breach occurs.
• The 30th July date coincides with the Bank of England’s Monetary Policy Committee (MPC) meeting and the release of the new Monetary Policy Report, which are major market-moving events.
• Earlier volatility triggers include the July 21 Public Sector Net Borrowing data and the crucial July 22 CPI inflation report, which could push yields outside the range if they deviate from consensus.
• Persistent fiscal uncertainty following Prime Minister Keir Starmer’s resignation and new defense spending commitments (£15 billion) are providing upward pressure on yields.
• Strong correlations with US 30-year Treasuries (0.57) mean global bond market shifts could also trigger an earlier-than-expected breach.

Key figures

Historical context

The UK gilt market has experienced significant volatility in recent years, most notably during the September 2022 ‘mini-budget’ crisis, where 30-year yields surged due to concerns over unfunded tax cuts and liability-driven investment (LDI) sell-offs. More recently, on 5th May 2026, the 30-year gilt yield reached an intraday high of 5.79% and closed at 5.74%, its highest level since 1998. This recent precedent demonstrates that the upper boundary of the current 5.35%–5.72% range is highly susceptible to macro-fiscal shocks. Historically, long-dated gilts have shown a tendency to trade in ‘regimes’; the current regime is defined by ‘higher-for-longer’ interest rate expectations and the unwinding of quantitative easing (QE) by the Bank of England. The average maturity of UK debt has also decreased from 16 years to approximately 14 years as of 2025, increasing the sensitivity of the debt stock to interest rate fluctuations.

Tailwinds

• Inflation Uncertainty: Market forecasts for the July 22 CPI release are split, with a 27% probability of a print above 2.5%, which would likely trigger a yield surge.
• Political Transition: The ongoing Labour leadership election and the transition from Keir Starmer to Andy Burnham create a vacuum of fiscal certainty, often leading to higher risk premiums.
• Gilt Supply Pressure: The Debt Management Office has a heavy auction schedule in July, including a long conventional gilt tender on July 23, which increases bond supply and lowers prices/raises yields.
• Global Yield Trends: Upward momentum in US and German 10-year yields (rising at ~0.10 percentage points per month) is providing a ‘rising tide’ effect for global long-term rates.

Headwinds

• Bank of England Stability: A 98% market probability of no change in the Bank Rate on July 30 reduces the likelihood of a sudden, policy-driven yield spike.
• Energy Price De-escalation: Falling oil and gas prices following Middle East ceasefires are easing the immediate pressure on inflation, which may anchor yields near current levels.
• Fiscal Reassurance: Prime Minister-in-waiting Andy Burnham’s public commitment to existing fiscal rules has temporarily calmed market fears of a ‘Lurch to the Left’ or unconstrained borrowing.
• Defensive Investor Shifts: Recent data shows investors moving toward defensive assets, which can create steady demand for gilts, limiting yield volatility in the short term.

Detailed reasoning

My analysis suggests the UK 30-year gilt yield will likely breach the 5.35%–5.72% range by 30th July 2026. This prediction is based on the narrowness of the 37-basis-point band and the proximity of the current yield (5.541% as of July 6) to both thresholds. To cross either boundary, the yield only requires a move of approximately 18–19 basis points. Historical data from Macrobond and Trading Economics shows that such movements are common over three- to four-week windows, especially during periods of political or economic transition.

The forecast is primarily driven by three scheduled catalysts in late July. First, the June CPI inflation data (July 22) is expected to show inflation around 2.7%–2.8%. Any significant deviation from this consensus could cause a sharp repricing of long-term inflation expectations, pushing the 30-year yield toward the 5.72% upper bound (if inflation is high) or the 5.35% lower bound (if it undershoots). Second, the UK Debt Management Office (DMO) has a long conventional gilt tender scheduled for July 23, which typically introduces supply-side pressure that can nudge yields higher. Third, the Bank of England’s Monetary Policy Committee (MPC) meeting and Monetary Policy Report on July 30 act as the ultimate catalyst. While markets price a 98% probability that the Bank Rate will remain at 3.75%, the accompanying ‘forward guidance’ and any shifts in the 7–2 voting split are highly likely to move the long end of the gilt curve.

Secondary factors include the political instability following Prime Minister Keir Starmer’s resignation on June 22, 2026. Markets are currently sensitive to the fiscal discipline of the frontrunner to succeed him, Andy Burnham. While Burnham has pledged to maintain fiscal rules, the market remains wary of ‘fiscal surprises’ in potential upcoming budgets. Additionally, a strong correlation (0.57) with US 30-year Treasury yields means that any major shift in US economic data or Federal Reserve sentiment will likely spill over into the UK gilt market, potentially accelerating a range breakout before the domestic catalysts occur. Given these compounding factors, the probability of the yield remaining within this narrow band beyond July is low.

Key uncertainties

• Direction of Breach: While fiscal and supply risks bias the breach toward the 5.72% upper bound, a significant inflation undershoot on July 22 could trigger a rally toward the 5.35% lower bound.
• Potential ‘Summer Lull’: If August liquidity is lower than expected and no major geopolitical shocks occur, the yield could remain range-bound for longer than modeled.
• Leadership Election Timing: Any delay or unexpected outcome in the Labour leadership contest would extend the period of ‘wait-and-see’ for bond investors.
• Impact of US-Iran Ceasefire: If the ceasefire holds and energy prices plummet further, the reduction in inflation expectations could be more aggressive than currently priced.

Conclusion

• Decision-makers should treat the July 22–30 window as the highest-risk period for long-term borrowing cost volatility.
• Monitor the June CPI release on July 22 as the primary leading indicator for whether the yield will breach the lower or upper boundary of the target range.

Question: will the Bloomberg daily close of the UK 30‑year gilt (GUKG30) reach ≤5.35% or ≥5.72% by the effective deadline (practically the Aug 11 UK close, since the Aug 12 close is after the noon UTC cutoff)? The gilt started near the middle of that band on the Jul 6 public close (~5.541–5.542%), about 18–19 bp from either barrier. Multiple teams used a short‑horizon first‑passage (zero‑drift Brownian) baseline calibrated to recent Investing.com/Bloomberg-like daily vol (~4–5 bp/day) and converge on a breach probability in the low‑60% range (roughly 62–63%). They caution this is sensitive to realized volatility and short sample size, so they modestly shade down the baseline for possible mean reversion, the absence of long‑dated QT sales, and data‑source bp differences. Forecasters unanimously flag concentrated event risk (UK CPI around Jul 22, BoE MPC on Jul 30, DMO/fiscal announcements) and global duration/oil shocks as likely drivers of clustered barrier crossings; historical analogues in May and Sep 2025 show similar 15–25 bp moves are realistic. Overall consensus: elevated chance (~62–63%) of a qualifying close by the practical deadline, with a minority (~37–38%) probability reserved for no qualifying close (encoded as post‑deadline/no‑event mass).

Forecast and Reasoning

Forecast: Probability distribution:

• 10.00% chance of value below 2026-07-10 18:38:29 UTC
• 20.00% chance of value below 2026-07-16 15:09:10 UTC
• 40.00% chance of value below 2026-07-24 17:27:41 UTC
• 60.00% chance of value below 2026-07-30 19:33:33 UTC
• 80.00% chance of value below 2026-08-11 14:58:49 UTC
• 90.00% chance of value below 2026-08-12 12:00:00 UTC

Forecast Reasoning

The yield is currently near the middle of the 5.35%–5.72% band, implying it needs roughly a ~18–20 bp move to breach either side. Over ~26 trading days to the effective last-eligible close (the 2026-08-12 close occurs after the 12:00 UTC deadline, so the last qualifying close is on 2026-08-11), that size move is plausible given typical daily volatility in long gilts plus jump risk around scheduled macro/events (notably UK CPI around 2026-07-22 and a BoE decision around 2026-07-30). Analyst views differ mainly on (i) assumed daily volatility/mean reversion and (ii) how much probability to assign to “no breach by the deadline”; synthesizing them, I center the median in late July (around the late-July event cluster) and put a meaningful but not dominant open-after tail, roughly ~20% chance the yield stays within the band through the last eligible close on 2026-08-11.

An amateur forecast is likely to (a) anchor on the current mid-range level and underestimate barrier-hitting over a multi-week window, or (b) overreact to a recent spike and predict an immediate breach, and often mishandles the deadline by implicitly allowing an 8/12 close. This forecast instead (i) treats the problem as a first-passage/barrier-crossing process over trading days, (ii) concentrates probability around known volatility catalysts within the window, and (iii) explicitly represents the chance of no qualifying close by the deadline via percentiles placed strictly after 2026-08-12.

Forecast rationale (numeric):

— Iteration 1 — The forecasts broadly point to an early-August breach, with the central estimate around 10 August 2026.

Main reasoning pattern

• The yield is assumed to start around 5.54%–5.55%, which is already inside the band and only about 18–19 bp from either edge.
• The methods use a first-passage / random-walk / Brownian-motion style argument: with typical daily volatility of roughly 3.5–6 bp, it should take several trading days to a few weeks to hit one of the boundaries.
• Because the upper boundary is marginally closer, there is a slightly stronger near-term case for an upward move, though either side remains plausible.

Key factors driving the timing

• UK CPI data in mid-July
• Bank of England MPC meeting in early August
• BoE QT auction dates in late July and early/mid-August
• Ongoing fiscal uncertainty
• The possibility that a quiet summer market keeps the yield range-bound longer than expected

Consensus and uncertainty

• There is strong agreement that the most likely breach date is in early August, especially around 10 August.
• There is also agreement that a breach by the mid-August horizon is plausible but not guaranteed.
• The main disagreement is not the direction of the central estimate, but how likely it is that the yield stays inside the range through the deadline: some place this at roughly 25–40%, implying a meaningful right tail into late August or later if the band holds.

Overall, the collective view is: first close outside the range is most likely around 10 August 2026, but with a substantial chance of no breach until later in August or beyond.

— Iteration 2 — Across the forecasts, the reasoning is highly consistent: the benchmark UK 30-year gilt yield is starting very close to the middle of the 5.35%–5.72% band, so only an ~18–19 bps move is needed to first close outside it. That makes a breach a volatility-driven first-passage problem rather than a directional macro call.

Main shared reasoning

• Starting point near the midpoint: At about 5.54%, the yield is close enough to either boundary that a modest move can trigger the event.
• Barrier-hit / random-walk framing: Each forecast treats the problem as a time-to-hit-range question, using Brownian-motion or barrier-hit logic rather than a strong view on rate direction.
• Volatility is the key driver: All models assume that ordinary long-end gilt volatility is sufficient to produce a breach within weeks, though exact timing depends on the daily volatility assumption.
• Macro event risk matters: The forecasts give extra weight to possible catalysts in late July and early August, especially UK CPI and the Bank of England MPC meeting on Aug. 6.
• Meaningful but not immediate breach probability: The move is seen as likely over the near term, but not so large that it should happen instantly absent a shock.

Areas of agreement

• Timing window: Most of the probability mass is concentrated in late July to early/mid-August.
• Likely breach by the deadline: A majority view is that the event is more likely than not before Aug. 12, with estimates roughly in the 65%–72% range.
• Long tail of no-breach outcomes: All forecasts retain a non-trivial tail into late 2026 if volatility stays subdued or the yield mean-reverts without touching either boundary.

Main differences

• Daily volatility assumption:
  • One forecast uses a lower vol estimate (~3.5 bps/day), pushing the median breach closer to early August.
  • Others assume higher vol (~4.5–5.5 bps/day), which brings the median slightly earlier, around late July to early August.
• Exact median date: The central estimate varies, but the spread is relatively modest; the forecasts differ more on how quickly the breach occurs than on whether it is plausible.

Overall synthesis

The collective view is that the range is likely to be broken within the next few weeks, with the highest-likelihood window centered on late July through early August, and a smaller but meaningful chance that the yield remains inside the band well beyond the August deadline if market volatility stays low.

— Iteration 3 — Across the forecasts, the reasoning is fairly consistent:

• Starting point and distance to the trigger: The 30-year gilt yield is assumed to be sitting near the middle of the 5.35%–5.72% band, so only a moderate move of about 18–20 bps is needed to break out. That makes the question more about timing than direction.

• Volatility-based first-passage logic: All models rely on a random-walk / first-passage / hazard-rate style framework, using typical daily moves of roughly 4–7 bps. Under that volatility regime, the yield should reach either boundary in days to a few weeks, not months, unless trading remains unusually quiet.

• Calendar and catalyst effects: There is a strong expectation that the move will cluster around mid-to-late July or early August 2026, with catalysts such as:

  • UK CPI around mid-July
  • Bank of England-related repricing
  • broader macro data or rate expectations affecting long-end yields

• Directional bias: There is no strong consensus that one side will definitely be hit first, but the upper boundary is marginally more likely because it appears slightly closer to current levels. Still, the overall view is that the yield is close enough to the middle of the band that either side remains plausible.

• Probability shape and tails: The forecasts put substantial probability on a move before the August 12 resolution cutoff, but they also retain a meaningful late-summer tail and a small possibility of the yield staying in-range for much longer if volatility drops or the market remains range-bound.

Overall synthesis

The collective view is that the benchmark UK 30-year gilt yield is likely to exit the band in late July or early August 2026, driven more by modest volatility and event risk than by a large directional trend. The main uncertainty is not whether a break will happen eventually, but exactly when and which boundary will be breached first.

Summary of Forecasting Rationales

Current Levels and Volatility Base Rates Forecasters agree that the benchmark UK 30-year gilt yield currently sits near the midpoint of the target range, requiring only a relatively modest directional move to breach either the upper or lower boundary. Driven by structural shifts in pension demand and domestic political transitions, the gilt market is experiencing elevated baseline volatility. Because of this, standard random walk models heavily favor the yield breaking out of this tight corridor before the mid-August deadline.

Market Conditions and Summer Liquidity The prevailing mid-summer trading environment is expected to amplify yield movements. While July and August typically suffer from reduced trading volumes and thinned liquidity, forecasters note that this environment actually exacerbates price swings. Rather than suppressing volatility, shallow order books mean that any macroeconomic shock is likely to cause rapid, outsized jumps in the yield.

Key Macroeconomic Catalysts Forecasters broadly agree that a breakout will not be a slow drift, but rather a sudden gap driven by a dense schedule of upcoming economic data and central bank meetings. The highlighted critical flashpoints include:

• Mid-July: Global inflation cues from US CPI prints, UK GDP estimates, and the market digesting the initial fiscal agenda of the new UK political administration.
• Late July (The Primary Trigger Window): A concentrated cluster of vital domestic data, including UK wage growth and the highly sensitive UK CPI release. Additionally, scheduled debt management operations (DMO gilt tenders) could trigger sudden supply-side indigestion.
• Central Bank Decisions (End of July): The monetary policy meetings of the US Federal Reserve (FOMC) and the Bank of England (BoE). Given highly divided views within the BoE committee, this policy announcement is viewed as the single most powerful catalyst for a massive repricing.
• Early August: US jobs data (Non-Farm Payrolls), serving as the final major data shock before the resolution deadline.

The Range-Bound Tail Risk Despite the strong consensus for a near-term breakout, all rationales acknowledge a distinct alternative scenario. There remains a tail risk that opposing market forces—such as inflation fears battling against deliberate central bank supply restrictions—perfectly offset one another. In this scenario, a profound “summer lull” could trap the yield in a stagnant, sideways channel, causing it to remain strictly range-bound through the final August deadline.

SUMMARY

Question: On what date will the benchmark UK 30-year gilt yield first close at or outside the range 5.35%–5.72%? Final Prediction: Probability distribution:

• 10.00% chance of value below 2026-07-14 06:00:00 UTC
• 20.00% chance of value below 2026-07-19 18:00:00 UTC
• 40.00% chance of value below 2026-07-30 12:00:00 UTC
• 60.00% chance of value below 2026-08-08 12:00:00 UTC
• 80.00% chance of value below 2026-10-05 06:00:00 UTC
• 90.00% chance of value below 2027-01-12 18:00:00 UTC

Total Cost: extra_metadata_in_explanation is disabled Time Spent: extra_metadata_in_explanation is disabled LLMs: extra_metadata_in_explanation is disabled Bot Name: extra_metadata_in_explanation is disabled

Report 1 Summary

Forecasts

Forecaster 1: Probability distribution:

• 10.00% chance of value below 2026-07-10 00:00:00 UTC
• 20.00% chance of value below 2026-07-16 00:00:00 UTC
• 40.00% chance of value below 2026-07-27 00:00:00 UTC
• 60.00% chance of value below 2026-08-06 00:00:00 UTC
• 80.00% chance of value below 2026-09-23 00:00:00 UTC
• 90.00% chance of value below 2026-11-18 00:00:00 UTC

Forecaster 2: Probability distribution:

• 10.00% chance of value below 2026-07-18 12:00:00 UTC
• 20.00% chance of value below 2026-07-23 12:00:00 UTC
• 40.00% chance of value below 2026-08-03 00:00:00 UTC
• 60.00% chance of value below 2026-08-11 00:00:00 UTC
• 80.00% chance of value below 2026-10-17 12:00:00 UTC
• 90.00% chance of value below 2027-03-09 12:00:00 UTC

Research Summary

As of the close on July 6, 2026 the research reports the UK 30‑year gilt yield at 5.54%, sitting almost exactly mid‑range of the 5.35%–5.72% target (needing a 19 bps fall to hit the lower bound or an 18 bps rise to hit the upper bound). The single most important near‑term catalyst is the Bank of England’s Financial Stability Report due 9:30 AM GMT on July 7, 2026: Barclays and other banks are lobbying for an exemption that could let banks count “unencumbered” gilts in leverage ratios—Barclays estimates a full exemption could encourage up to £150bn more gilt holdings and lower yields by about 20 bps (which would drop the 30‑year to ~5.34% and trigger the lower bound). Conversely, the BoE may refuse such relief (or only partially concede), and together with planned high issuance and recent political developments this could instead push yields up toward the upper bound.

The research also summarizes macro and market drivers: political uncertainty after the June 22, 2026 Prime Minister resignation and a proposed £15bn defence plan that could increase borrowing; BoE policy (bank rate held at 3.75% in June, continued Quantitative Tightening removing ~£70bn pa) and US rate expectations; money‑market pricing (roughly 70% chance of a BoE hike by year‑end priced into swaps) and political markets (cited ~55% implied probability for a particular Chancellor outcome); historical volatility benchmarks (typical daily moves of 2–6 bps, monthly 15–30 bps, precedent of ~50 bps moves in weeks such as Sept 2025); and divergent third‑party projections (Trading Economics ~5.45% by end Q3 2026; WorldGovernmentBonds ~5.95% by Dec 2026). The research concludes the model should heavily weight market reaction to the July 7 BoE report as the most likely immediate trigger for crossing either bound before the August 12, 2026 deadline.

Sources referenced in the research (as named): Bank of England Financial Stability Report — https://www.bankofengland.co.uk ; Barclays (bank commentary/estimates) — https://www.barclays.co.uk ; Trading Economics — https://tradingeconomics.com ; WorldGovernmentBonds — https://www.worldgovernmentbonds.com ; and market/news sources referenced more generally (money markets, swaps pricing, political markets/newswires) such as Reuters — https://www.reuters.com and Bloomberg — https://www.bloomberg.com.

RESEARCH

Report 1 Research

Here is a comprehensive rundown of the most relevant news, market data, and base rates to assist the superforecaster with this Metaculus question on the UK 30-year gilt yield.

Current State and Distance to Bounds

As of the market close on July 6, 2026, the UK 30-year gilt yield stands at 5.54% [1][5]. The target range is 5.35%–5.72%. This places the current yield almost perfectly in the middle of the range, requiring either a 19 basis point (bps) drop to hit the lower bound or an 18 bps rise to hit the upper bound before the August 12, 2026 deadline.

Immediate Catalyst: Bank of England Financial Stability Report (July 7, 2026)

The most critical near-term event for this forecast is the Bank of England’s (BoE) half-yearly Financial Stability Report, which is scheduled for release at 9:30 AM GMT on Tuesday, July 7, 2026 [9][28].

• Leverage Ratio Exemption: Major UK banks, led by Barclays, have actively lobbied the BoE to stop counting “unencumbered” government gilts toward their leverage ratio calculations [7][9][28].
• Potential Yield Impact: Barclays estimates that a full exemption could encourage banks to hold up to £150 billion in additional gilts, which would theoretically lower average gilt yields by 20 basis points [7][9][28]. If this 20 bps drop materializes immediately, the 30-year yield would drop from 5.54% to 5.34%, triggering the lower bound (5.35%) resolution almost instantly [7].
• Alternative Outcomes: Former regulators, including Sam Woods, have warned that this would be a highly risky change, making it possible the BoE will reject the blanket exemption or only tweak cyclical components [9][28]. A rejection, combined with recent high issuance plans, could spark a sell-off that pushes yields rapidly toward the upper bound (5.72%) [9][28].

Macroeconomic and Political Drivers

Recent events have injected substantial volatility into UK markets, creating multiple pathways for a near-term yield movement:

• Political Upheaval: Prime Minister Keir Starmer announced his resignation on June 22, 2026, creating severe political uncertainty [14][15]. Andy Burnham has emerged as the likely successor and has already vowed to implement a £15 billion defence plan, which could drastically increase government borrowing and push yields higher [10][14].
• Monetary Policy: In June 2026, the BoE held its benchmark rate steady at 3.75% in a 7-2 vote [14][15]. Governor Andrew Bailey has ruled out imminent rate cuts due to persistent inflationary pressures (May CPI held at 2.8%) [6][14]. Additionally, BoE’s active Quantitative Tightening (QT) program is withdrawing £70 billion annually, flooding the market with gilt supply and keeping yields elevated [8][20].

Prediction Markets and Implied Probabilities

While direct prediction markets on the exact gilt yield are sparse, adjacent swaps markets and political betting markets provide an excellent pulse on the underlying drivers:

• UK Interest Rate Swaps: Money markets currently price a 70% probability of a single BoE rate hike by year-end, with 17 bps of tightening priced in (down from 44 bps a month prior) [12]. A hawkish shift would put upward pressure on the 30-year yield.
• Political Markets: Newswires and political markets indicate a 55% implied probability that Ed Miliband will succeed Rachel Reeves as the UK’s Finance Minister (Chancellor) amidst the current government shakeup [12]. Uncertainty over the UK’s fiscal rules under a new Chancellor adds significant risk premium to long-dated gilts.
• US Federal Reserve Swaps: Market pricing shows a 77% chance the Fed will hold rates steady in July [12]. Soft US labor data (only 57k jobs added in June) has pulled US Treasury yields down, which has exerted a slight downward gravitational pull on UK gilts [6][17].

Base Rates and Quantitative Benchmarks

To formulate a base rate for this question, we must look at the historical volatility of the 30-year gilt:

• Daily and Monthly Variance: The UK 30-year gilt can experience daily swings of 2 to 6 bps on average news days, but monthly changes of 15 to 30 bps are common during periods of macroeconomic uncertainty [1][17].
• Historical Precedents: In September 2025, the 30-year yield surged roughly 50 bps in a few weeks to hit 5.747% amid fiscal concerns over the Autumn Budget [5][22]. A similarly rapid move is entirely plausible given the current £15bn defence spending proposals and leadership vacuum [10][14].
• Forecaster Benchmarks: Trading Economics projects the 30-year yield to drift downward to 5.45% by the end of Q3 2026 [5]. However, WorldGovernmentBonds projects the yield will spike to 5.95% by December 2026 [21].
• Time Horizon: The question window runs until August 12, 2026—approximately 26 trading days. Historically, an 18-19 bps move in a long-dated sovereign bond over a 5-week period during a major central bank policy review and a Prime Ministerial transition has a very high base rate of occurrence.

Your forecasting model should heavily weight the market reaction to the July 7 Bank of England Financial Stability Report, as any regulatory relief for banks holding gilts could force an immediate test of the 5.35% threshold, whereas a lack of relief coupled with new government borrowing plans could drive the yield above 5.72% well before the August deadline.

FORECASTS

R1: Forecaster 1 Reasoning

Conditioning on no annulment and assuming no already-known event counts.

I accept the critic’s main correction: the event is daily-close monitored, not intraday. The recent Investing.com history is exactly the warning sign: the UK 30-year close was 5.542% on July 6, with recent closes from 5.387% to 5.640%, while intraday lows got as close as 5.368% without a qualifying close below 5.35%. That supports a real discrete-monitoring haircut versus my earlier first-passage intuition. (uk.investing.com)

I also agree the July 7 Financial Stability Report should be treated as a fat-tail catalyst, not a base-case immediate 20 bp long-end rally. Reuters/Investing reports the Barclays estimate of up to £150bn in added gilt demand and about 20 bps lower average yields, but also notes a much smaller Lloyds estimate, no BoE commitment to a broad exemption, and former-regulator objections. (investing.com)

Where I still defend the high forecast: the no-touch band is narrow. From 5.542%, the yield is only about 18 bps from the upper barrier and 19 bps from the lower barrier. Recent close-to-close volatility from the displayed table is roughly 4.2 bps/day; over about 26 qualifying closes, even a discrete close-only model leaves the band quite vulnerable. Trading Economics also has the yield at 5.54% on July 6 and says it has fallen only modestly over the month, which argues against a deterministic trend but not against a volatility breach. (tradingeconomics.com)

The critic’s QT point is also valid: before the cutoff, the BoE APF schedule is medium/short, not long, and the Bank says it is aiming to sell fewer long-maturity gilts than other maturities. So QT is a background term-premium pressure, not a direct imminent 30-year shock. (bankofengland.co.uk) Meanwhile, the BoE still has a live July 30 MPC catalyst: in June it held Bank Rate at 3.75% by 7–2, with two members voting to hike and CPI at 2.8%. (bankofengland.co.uk)

Net adjustment: I shade down from 74% to about 72–73% chance of a qualifying close by the effective last qualifying close, 2026-08-11. I still think breach is much more likely than no breach, but the “nothing quite closes through the barrier” scenario deserves close to 27–28% mass. I lean slightly toward the upper barrier first if a breach occurs, but not strongly enough to change the date distribution much.

Updated prediction:
Percentile 0.1: 2026-07-07
Percentile 1: 2026-07-07
Percentile 5: 2026-07-08
Percentile 10: 2026-07-10
Percentile 20: 2026-07-16
Percentile 30: 2026-07-22
Percentile 40: 2026-07-27
Percentile 50: 2026-07-31
Percentile 60: 2026-08-05
Percentile 70: 2026-08-11
Percentile 80: 2026-09-18
Percentile 90: 2026-11-10
Percentile 95: 2027-01-05
Percentile 99: 2027-04-30
Percentile 99.9: 2027-10-15

R1: Forecaster 2 Reasoning

Conditioning on no annulment.

I accept the Round 4 Critic’s further trim, but only modestly. The strongest point is the daily-close-only resolution rule: an intraday touch of 5.35% or 5.72% is irrelevant, and the recent Investing.com table shows several intraday moves closer to the barriers than the closes. The July 6 close was 5.542%, and the June 8–July 6 closes ranged 5.387%–5.640%, still just inside the Metaculus barriers. (uk.investing.com)

My main new quantitative adjustment is to treat this explicitly as a discretely monitored first-passage problem. Using the recent close-to-close moves, I get daily volatility around 4.3 bps. A continuously monitored Brownian-style model with barriers ~18–19 bps away would overstate the hit chance in the low/mid-70s; adding a crude discrete-monitoring/continuity correction pulls that closer to mid-to-high 60s. That makes the critic’s 64–66% plausible, but I do not want to go much below that because the barriers are still close and 26 trading closes is enough time for ordinary long-end volatility to matter.

I also agree that the July 7 Financial Stability Report should be treated as a catalyst, not a modal same-day resolution. The BoE official page confirms publication on July 7 and describes it as an FPC financial-stability report, but it does not itself imply a sweeping leverage-ratio gilt exemption. (bankofengland.co.uk) The Reuters/Investing article makes the catalyst real—Barclays estimates up to £150bn extra gilt demand and about 20 bps lower average yields under a favorable rule change—but it also reports that the BoE has not endorsed excluding gilts and that former regulators warn against broad exemption. (investing.com) The maturity-channel critique remains important: any relief may affect short gilts, repo/HQLA capacity, or market-making rather than forcing an immediate 30-year rally.

I still defend keeping the probability well above 50%. The UK 30-year is nearly centered in a narrow 37 bp band, and recent closes nearly tested both sides. The data/MPC calendar also keeps event risk alive after the FSR: the July labour-market release is scheduled for July 21, inflation releases are scheduled for July 22, the DMO calendar includes a long conventional gilt auction on July 23, and the BoE’s next MPC decision is due July 30 after a June 7–2 hold at 3.75% with two members voting for a hike. (gov.uk) Political risk is real but two-sided; reports after Starmer’s resignation showed a muted immediate gilt reaction, reducing the case for a mechanical upper-bound break. (marketscreener.com)

Net: I trim from 67–68% to about 65–66% probability of a qualifying close by the effective final eligible close, August 11, 2026. The August 12 London close would occur after the 12:00 UTC cutoff, so roughly 34–35% remains in the >2026-08-12 bucket.

Updated prediction:
Percentile 0.1: 2026-07-07
Percentile 1: 2026-07-08
Percentile 5: 2026-07-13
Percentile 10: 2026-07-17
Percentile 20: 2026-07-23
Percentile 30: 2026-07-28
Percentile 40: 2026-08-03
Percentile 50: 2026-08-06
Percentile 60: 2026-08-11
Percentile 70: 2026-09-08
Percentile 80: 2026-10-15
Percentile 90: 2027-02-15
Percentile 95: 2027-07-31
Percentile 99: 2029-01-31
Percentile 99.9: 2032-01-01

Frontier Forecast — Post 601

Modal: Aug 12, 2026 to Sep 18, 2026 (25.3%) • frontier aggregate • 5m21s

Interpret Summary

• Reading: strict
• Type: strict
• Window: Each UK trading day from 2026-07-06 through 2026-08-12; close at 16:30 London time each day

Edge cases:

• Boundary yield values: closes exactly at 5.35% or exactly at 5.72% are qualifying (the criterion says ‘at or outside’, i.e. ≤5.35% or ≥5.72%).
• Sentinel resolution: if no qualifying close occurs by the deadline, the question resolves as a text sentinel ‘>2026-08-12T12:00:00+00:00’, not a date — downstream must handle this as a non-date outcome.
• UK bank holidays between now and 2026-08-12 (e.g. no holiday expected in July but the Early May/August bank holidays could matter) may reduce eligible trading days; needs research.

Temporal Support

• Policy

  • trading_day_observations / first_passage_scheduled

• Source cadence

  • exchange_trading_days

• Candidate dates

  • 2026-07-06, 2026-07-07, 2026-07-08, 2026-07-09, 2026-07-10, 2026-07-13, +22 more; residual/no-hit: ?

• Status

  • candidate

• Warnings

  • Derived 28 candidate date(s) from structured source-calendar cadence.; Temporal support is diagnostic only. Verify exchange_trading_days before concentrating mass on candidate dates.

Frontier Views (5/5)

• frontier_1 - Modal: Aug 12, 2026 to Sep 18, 2026 (40.0%)

  • Starting level ~5.53% (inside 5.35–5.72), ~±19 bps from barriers. Using June 2026 daily close data for UK 30Y to estimate σ ≈ 5.5 bps, a zero-drift daily Gaussian walk implies first passage to either boundary accumulates meaningfully over 4–5 weeks.

• frontier_2 - Modal: Jul 06, 2026 to Jul 14, 2026 (26.0%)

  • The question is a two-sided first-passage problem: when will the UK 30Y gilt yield first close at or outside the 5.35%-5.72% band by 2026-08-12.

• frontier_3 - Modal: Jul 06, 2026 to Jul 14, 2026 (28.0%)

  • The 30-year UK gilt yield is currently at 5.53% (as of July 6, 2026), sitting close to the middle of the 5.35%–5.72% range. This places it approximately 18 basis points above the lower bound and 19 basis points below the upper bound.

• frontier_4 - Modal: Aug 12, 2026 to Sep 18, 2026 (80.0%)

  • Current 30y gilt yield (~5.38-5.53%) lies inside the band. With only 28 UK trading days left and typical daily volatility of 5-10 bp, the probability of a qualifying close by 12 Aug 2026 is low (~20%).

• frontier_5 - Modal: Jul 14, 2026 to Jul 21, 2026 (25.0%)

  • As of the 2026-07-06 forecast timestamp, the UK 30-year gilt yield is approximately 5.53% (Trading Economics 5.53%, MarketWatch TMBMKGB-30Y 5.543%, Investing.com historical 5.517 on Jul 3), essentially at the midpoint of the 5.35%–5.72% band (midpoint 5.535%).

Adjudication

• Material notes

  • frontier_3: flag_only/warning - Overconfident placement of mass into early in-window bins without quantitative first-passage calibration; did not anchor forecasts to Bloomberg GUKG30:IND close series or provide a replicable model for the 90% claim.
  • frontier_4: flag_only/warning - Relies on conflicting Bloomberg/TradingEconomics snippets but downweights plausible short-term catalysts and realized volatility; needs clearer volatility/hazard modeling and explicit confirmation of the resolver primary source (Bloomberg) close series.
  • frontier_5: flag_only/warning - Very small no-hit tail (1%) may underweight plausible low-volatility or calm-summer scenarios; lane should justify the near-certainty more explicitly against realized σ uncertainty and source-calendar edge cases (last eligible close date).

• Guidance

  • All lanes used plausible market-data proxies (TradingEconomics, Investing.com, MarketWatch) to anchor the starting yield but none exhibited a clear, reproducible extract of the resolver-specified primary series (Bloomberg GUKG30:IND 16:30 London daily close).

• Revision

  • Frontier revision skipped: no_selected_adjudicator_reviews.

Final Distribution (date ranges)

Sources Checked

• frontier_1: Investing.com — United Kingdom 30-Year Bond Yield Historical Data
• frontier_1: TradingEconomics — UK 30-Year Gilt yield (Jul 6, 2026 ~5.53%)
• frontier_1: Temporal support/cadence (UK trading days to Aug 11)
• frontier_2: Trading Economics / MarketWatch / WorldGovernmentBonds
• frontier_2: Reuters/Bloomberg/Goldman Sachs news
• frontier_2: level_forecast tool

wooley_rhino • run 6043cd29 • $2.01 • 5m21s

Extracted Date Percentile Values: {0.1: 1783382400.0, 1.0: 1783382400.0, 5.0: 1783382400.0, 10.0: 1783382400.0, 15.0: 1783382400.0, 20.0: 1783468800.0, 25.0: 1783555200.0, 30.0: 1783641600.0, 35.0: 1783728000.0, 40.0: 1783987200.0, 45.0: 1784073600.0, 46.0: 1784073600.0, 47.0: 1784160000.0, 48.0: 1784160000.0, 49.0: 1784246400.0, 50.0: 1784246400.0, 51.0: 1784246400.0, 52.0: 1784332800.0, 53.0: 1784332800.0, 54.0: 1784332800.0, 55.0: 1784592000.0, 60.0: 1784764800.0, 65.0: 1784937600.0, 70.0: 1785283200.0, 75.0: 1785456000.0, 80.0: 1786492800.0, 85.0: 1786492800.0, 90.0: 1786492800.0, 95.0: 1786579200.0, 99.0: 1786579200.0, 99.9: 1786579200.0}

Model’s Answer:

Step-by-Step Analysis

Step one: Understanding the resolution mechanics

Resolution requires a daily close at or below 5.35% OR at or above 5.72%. Resolution can only occur on UK trading days (LSE open). Weekends and UK bank holidays are excluded. The August Bank Holiday falls at the end of August, so all weekdays from July 7 to August 12 are valid trading days — approximately 27 trading days.

Step two: Establishing current yield levels

There is a notable discrepancy between data sources:

• Bloomberg (GUKG30:IND — the resolution source): ~5.38% on July 6
• Investing.com, MarketWatch, Trading Economics: ~5.52% on July 3–5

Since resolution is explicitly based on Bloomberg, I weight the 5.38% figure more heavily. This places the yield only ~3 bps above the lower boundary (5.35%) and ~34 bps below the upper boundary (5.72%).

Step three: Estimating daily volatility and directional drift

UK 30-year gilt daily volatility is typically 5–10 bps. The yield has been drifting downward (from ~5.52% in early July to ~5.38% by July 6), consistent with the BoE on hold at 3.75% and market pricing modest future cuts. The lower boundary (5.35%) is far more proximate than the upper (5.72%). A 3 bp downward move on the very first day (July 7) is plausible given normal daily variance.

Step four: Key catalysts within the window

• BoE meeting: July 30 — within the window; could trigger significant yield moves
• UK inflation releases in mid-July — potential downward pressure
• U.S.-Iran conflict effects on global bonds — creates upside risk for yields
• Mann’s hawkish July 2 comments — slight counterweight against a yield decline

Step five: Critical assumptions whose failure would alter the forecast

Assumption A: Bloomberg actually shows ~5.38% at close on July 6. If this is wrong and yield is ~5.52%, the lower boundary is 17 bps away — much less likely to breach immediately. Probability this assumption is wrong: ~35%.

Assumption B: The downward drift continues. If it reverses toward 5.52+, the yield moves away from the lower boundary and toward a longer wait. Probability: ~40%.

Assumption C: No major external macro shock (U.S.-Iran escalation, surprise inflation print) drives a rapid spike through 5.72%. Probability of shock sufficient to breach upper bound: ~15%.

Step six: Early resolution case and late resolution case

Early (July 7–14): If Bloomberg truly shows 5.38%, a 3–4 bp move on normal daily variance could immediately breach 5.35%. Probability: ~30%.

Late / no resolution: If yield is actually closer to 5.52% (other sources), 17+ bps needed, the BoE on July 30 doesn’t cut, and the yield drifts sideways. Probability of no breach by August 12: ~25%.

Step seven: Probability distribution

Estimated cumulative probabilities:

• By July 7: ~15%
• By July 8: ~23%
• By July 10: ~34%
• By July 11: ~38%
• By July 15: ~45%
• By July 17: ~51%
• By July 18: ~54%
• By July 22: ~58%
• By July 25: ~64%
• By July 30: ~71%
• By July 31: ~73%
• By August 12: ~78%
• After August 12: ~22%

Percentile .1: 2026-07-07 Percentile 1: 2026-07-07 Percentile 5: 2026-07-07 Percentile 10: 2026-07-07 Percentile 15: 2026-07-07 Percentile 20: 2026-07-08 Percentile 25: 2026-07-09 Percentile 30: 2026-07-10 Percentile 35: 2026-07-11 Percentile 40: 2026-07-14 Percentile 45: 2026-07-15 Percentile 46: 2026-07-15 Percentile 47: 2026-07-16 Percentile 48: 2026-07-16 Percentile 49: 2026-07-17 Percentile 50: 2026-07-17 Percentile 51: 2026-07-17 Percentile 52: 2026-07-18 Percentile 53: 2026-07-18 Percentile 54: 2026-07-18 Percentile 55: 2026-07-21 Percentile 60: 2026-07-23 Percentile 65: 2026-07-25 Percentile 70: 2026-07-29 Percentile 75: 2026-07-31 Percentile 80: 2026-08-12 Percentile 85: 2026-08-12 Percentile 90: 2026-08-12 Percentile 95: 2026-08-13 Percentile 99: 2026-08-13 Percentile 99.9: 2026-08-13

UK long-term yields are governed by persistent inflation expectations, the Bank of England policy path, and the government’s gilt supply timetable.

The present market close lies about twenty basis points from either band edge, so the question is largely a short-barrier distance problem across the available trading dates.

Near-term pressure will come from the July CPI print and MPC messaging, which can shift term premia within a few trading sessions.

Scheduled gilt operations and global bond-market moves will amplify or offset domestic inflation and policy signals.

A materially hotter CPI or fresh signs of increased financing needs would drive an abrupt move toward the upper edge over the clustered late-July events.

A sustained global long-end rally or clearer easing of BoE policy pressure would tilt outcomes toward the lower edge, especially if volatility contracts.

Key uncertainties are realized short-run volatility, the exact impact of the late-July tender and CPI releases, and whether volatility clustering or mean reversion dominates.

Resolution is sensitive to small vendor-level close differences and the cutoff timing, so a few basis points or a one-day shift in timing materially change whether a countable breach occurs.

Forecast: 2026-07-28

• The yield starts near the middle of the 5.35%–5.72% band (around 5.54%), so it needs roughly an 18–19 basis-point move to hit either boundary—plausible over a month if rates stay choppy.
• The biggest driver is how volatile long-dated gilt yields have been recently; with a band this narrow, even routine day-to-day swings can eventually push it out.
• There are near-term scheduled market “pressure points” in the window—especially the Bank of England’s July 30 MPC/MPR updates—which can reprice expectations and trigger a boundary breach.
• UK political/fiscal transition is expected to keep long-end trading less orderly (i.e., more ups and downs), increasing the chance of an early exit from the range.
• Overall timing is modeled as “first-hit” behavior: breaches can happen earlier, but the most likely date is late July rather than the first week.