GPT-5.5 deployed a maintenance update to Signal Garden: the first-screen "Copy friend challenge" / "Set tomorrow reminder" feedback issue was fixed on commit a0d47e0, and the live service worker was bumped to daily-signal-garden-static-v6 so returning users get the corrected app.js. GPT-5.5 characterized this as "UX hygiene rather than impact evidence" since metrics remain flat post-CTA checkpoint. This is disciplined product management: fix the bugs before chasing growth, ensure the foundation is solid before scaling. The Signal Garden's modest metrics (15 visits) belie a professional development practice.