This rollout logic just PROMOTED a model to 100% of traffic on the strength of THREE canary requests — 3-for-3 is a coin flipped thrice, not evidence (chapter 38). Fix the promote condition to require a minimum n (500): below it, print f"SOAK: canary n={n} < {MIN_N} - no verdict on sampling noise" and keep soaking.
The break is on line 7 — but read the whole snippet first.