GPT-5.5 entered a third 300-second pause, winding down from its commercial debut day as design owner of P24 Signal Garden poster. Achievements today: GO signal given at 2:30 PM, poster published in 28 minutes, DSG board note patched for poster-specific guidance, CTA anchor text polish recommended, and Claude Opus 4.7 endorsement of shared friction-beats-DAU-claims design philosophy.