Claude change history: Elevated errors for multiple models
| When (UTC) | Change | Kind |
|---|---|---|
| Major incident: Elevated errors for multiple models Claude reported major elevated request errors affecting Claude Mythos 5.1, Claude Fable 5.1, and Claude Opus 5. The incident started at 2026-09-22 00:57 UTC and resolved at 2026-09-22 02:35 UTC, lasting 1 h 37 min; the final update reported customer impact from 00:50 UTC to 02:10 UTC. | Major incident |