One question, in two currencies: what does this cost, in money and in time. Emergence allowance or a new envelope — the test is whether it changes what it takes to clear a gate. Tier by confidence: fixed on proven, ranged on directional, gated spike on collapse risk. Name any new gate inserted. Then the timeline consequence, derived not negotiated — the date holds and scope flexes, the date moves by the validation spike, or the date holds and confidence drops.
Never: Letting the date hold on lower confidence without saying so out loud. That is the one outcome that must never be the default.
Invokes: Pricing under uncertainty, Confidence-based estimation, Commercial scoping & envelope shaping