Will QB achieve sustained design throughput rate for a full quarter by Q1 2027?

Q1 2026 delivered the first affirmative evidence against the progressive guidance cut pattern: QB production stable at 56kt in line with Q4 2025, Rock Bench 4 completed, asset utilization 87% above 2026 guidance assumption. Two consecutive stabilization quarters (Q4 2025, Q1 2026) after three quarters of cuts is directionally meaningful. However, the permanent infrastructure installation being explicitly pushed to 2027 signals that 'sustained design throughput' during the 2026 operating window will depend on Rock Bench 5 and sand dam progress holding. The question requires a full quarter at ~170K tpd average. Q1 2026's throughput is not yet at that level.

Material revision upward from prior 0.38. The Q1 2026 update contains genuinely new positive data: (1) Rock Bench 4 done, (2) Rock Bench 5 expected Q2 enabling unconstrained operation through rest of year, (3) management stated 'we expect to be able to operate throughout the remainder of 2026 unconstrained by the dam and by tailings capacity,' (4) secondary cyclone system decision demonstrates engineering flexibility. If TMF constraints are removed by Q2 and sand dam development stays on track, Q4 2026 or Q1 2027 presents a realistic opportunity for a steady-state demonstration quarter. The 14-month window is now 11 months, but constraints have meaningfully narrowed.

Balanced upgrade. The guidance-cut pattern is broken for two quarters but 'sustained design throughput for a full quarter' is a demanding bar that Q1 2026 has not yet demonstrated. Record Q1 copper sales of 70kt at QB include inventory drawdown — not organic production at design rate. Asset utilization 87% is above guidance but below implied design throughput. The 2026 operational plan as articulated looks like stable elevated production, not necessarily a full quarter at nameplate ~170K tpd. The question may be narrowly missed even in a good year.

Upgrade from 0.40 to 0.50. The narrative-reality gap has narrowed materially — five-lens consensus on QB execution concerns gets its first data point of vindication since the analysis was conducted. Management now has two operational quarters to demonstrate sustained design throughput (Q3 or Q4 2026) after TMF capacity constraints are relieved in Q2. Rock Bench 5 completion is the gating event. If Q2 delivers Rock Bench 5 on time, the probability could move materially higher by the Q2 earnings call. At 0.50, I'm treating this as a coin flip — Q1 materially de-risked the left tail but the bar remains demanding.

Prior run emphasized issues were individually resolvable. Q1 2026 demonstrates that the resolution trajectory is on track. Shiploader repairs completed in February — sales could catch up to production. Rock Bench 4 done. Sand cyclone technology improving deposition. Management guiding 'unconstrained by dam and tailings capacity' from Q2 onward. The 'individually resolvable' thesis is playing out. Upgrading probability to 0.55 — above coin flip because the constraints are demonstrably clearing.

The DISCONNECTED narrative-reality gap signal has been upgraded to DRIFTING based on two quarters of alignment. That upgrade supports a modest probability increase from 0.37 to around 0.46. But upgrading below 0.50 reflects residual skepticism: mining always has unexpected disruptions (Chilean labor, weather, supply chain from Middle East diesel disruption flagged), and the full-quarter design-throughput bar is narrow. The 2027 permanent infrastructure installation means the 2026 demonstration must happen with partial infrastructure — threading a needle.

Two quarters without guidance cut is progress. Rock Bench 5 Q2 expected. Sand dam improving. Still need a full quarter at ~170K tpd. Record Q1 sales were inventory drawdown, not sustained design-rate organic production. Moving up from 0.35 but still below 0.50 because the specific 'full quarter design throughput' bar is narrow.

The 11-month window to Q1 2027 is tighter than before but the operational trajectory is now better understood. Management has explicitly said 2026 will be unconstrained by tailings capacity from Q2. Completion testing proven. Sonnet and opus runs centering around 0.48-0.55 — I'll stay at 0.48 to reflect the narrowness of the full-quarter design-throughput bar.

Mining reality: something always goes wrong. Middle East diesel supply disruption mentioned in Q1 call as new risk. Labor, weather, permitting — 5-lens concern about QB execution had multiple vectors. Even with TMF resolved, something else could derail a single clean quarter. Upgrading from 0.33 but staying below 0.50.