GitHub change history: Degradation with Gemini 3.8 Flash

GitHub reported a major Gemini 3.8 Flash degradation in Copilot starting 2026-09-16 07:20 UTC, resolved at 2026-09-16 17:48 UTC (10 h 27 min). Requests failed at an average rate of 6.4% due to a capacity issue; mitigation was reported at 11:45 UTC. Other models were unaffected; users could switch models or use 'Auto'.