1- 2026-10-30 P0 contract written.2- 2026-10-30 P1 audit: clean balanced data, no exclusions.3- 2026-10-30 P2 baseline se_iid computed (naïve).4- 2026-10-30 P3 decision: main SE = CR1 cluster-robust by school with t(G-1=39) reference; robustness = school-means regression. No randomness, seed null.5- 2026-10-30 P4 verification and gate.6- 2026-10-30 P4/P5 passed; gate receipts 20261030T043629.457750Z.json recorded. Task complete.7