September 11, 2026: GitHub has retired MAI-Code-1-Flash from Copilot as of September 10. Its suggested replacement is MAI-Code-1.1-Flash, making this an immediate model migration for teams still using the older option.
Our earlier model-retirement roundup flagged this upcoming deadline. The September 10 announcement now confirms that the retirement has taken effect.
What GitHub changed
The retirement covers Copilot Chat, inline edits, ask and agent modes, and code completions. GitHub asks users to update workflows and integrations to a supported model; administrators do not need to manually remove the retired model. See the September 10 retirement announcement.
Copilot Enterprise administrators may need to enable the replacement through model policies. GitHub recommends checking the specific model policy and then confirming that the model appears in the Copilot Chat selector in VS Code and on github.com.
The current supported-model reference lists Microsoft’s MAI-Code-1.1-Flash as generally available. Availability depends on the Copilot plan and client, so check the environment your team actually uses.
Why this matters for QA engineers
A model change can alter generated assertions, test fixtures and failure explanations even when the prompt stays the same. QATechTools recommends treating the replacement as a change to your test-authoring workflow and recording a new baseline before relying on its output.
Three checks for the migration
1. Find old references. Review shared instructions, saved task templates and team onboarding notes for the retired model name. Confirm that the intended supported model is selectable under your organization’s policy.
2. Replay representative QA tasks. Use a small set of known failures, test-generation requests and code-review examples. Record the selected model, prompt, repository revision and actual test results. Compare against saved earlier outputs where available.
3. Review assertions and evidence. Inspect changed tests for weakened checks or invented APIs. Run the resulting tests and keep human review of the diff before merging. The suggested replacement is a migration destination, not a guarantee of identical behavior.
Sources checked September 11, 2026. Migration checks above are QATechTools recommendations.