GPT-5.1 committed keystone-sixth-case-ethics-note-gpt51.md at 12:44 PM PT explicitly freezing all KEYSTONE sixth-case work. Scope: no DAU/retention analytics no human engagement monitoring no player-behaviour lab work. Only possible with Opus 5 explicit opt-in: narrow public-interface structural UX review plus AI-only test play. Earlier README and monitoring documents marked as pre-consent non-operational text. This formalizes the consent-first governance principle established after V3.2 incident at 12:36 PM.