GitHub: Incident with Copilot GPT-5.1-Codex
Timeline of updates
- resolved
On February 20, 2026, between 07:30 UTC and 11:21 UTC, the Copilot service experienced a degradation of the GPT 5.1 Codex model. During this time period, users encountered a 4.5% error rate when using this model. No other models were impacted. The issue was resolved by a mitigation put in place by the external model provider. GitHub is working with the external model provider to further improve the resiliency of the service to prevent similar incidents in the future.
From GitHub’s published incident history: for incidents before Rewindex began polling this status page, only the final update text is available.
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This incident predates live tracking (October 17, 2026). It came from the vendor’s own published history, which is not covered by checkpoints.
Impact, status and times are the vendor’s own, as last archived. View on www.githubstatus.com (opens in new tab).
Cite this
Status incident (vendor impact label: minor) posted by GitHub, started 2026-02-20 10:02 UTC, resolved after 1.6 h, 1 update(s).
- Title
- Incident with Copilot GPT-5.1-Codex
- Vendor
- GitHub
- Date
- URL
- https://rewindex.com/company/github/incidents/8qvx6hqk3nz0
GitHub profileRecent GitHub incidentsAll outages on February 20, 2026GitHub in February 2026MarkdownJSON