GitHub Copilot retires four models, with named replacements

GitHub’s changelog for 2 October 2026 says four models are deprecated across GitHub Copilot as of that day. The list covers Copilot Chat, inline edits, ask mode, agent mode, and code completions. GitHub’s table pairs each retired model with a suggested alternative:

Deprecated on 2 October 2026	Suggested alternative
Gemini 3.5 Flash	Gemini 3.8 Flash
Gemini 3.6 Flash	Gemini 3.8 Flash
Kimi K2.7 Code	Kimi K3
Claude Opus 4.7	Claude Opus 5.5

The post says no action is required to remove the deprecated models. They leave the product. What you may have to do is point workflows and integrations at a model that is still offered, and, on Copilot Enterprise, enable the replacement in the model policy. GitHub says an administrator can check an individual Copilot settings page to see that the policy allows the model, and that once it is allowed the model shows up in the Copilot Chat model picker in VS Code and on github.com. Enterprise customers with questions are told to contact their account manager.

What the changelog leaves unspecified

The changelog does not give a grace period after 2 October, a list of API error strings, or prices for the replacements. It also does not say the replacement models are new that day. Gemini 3.8 Flash, Kimi K3, and Claude Opus 5.5 are named only as the models GitHub suggests you use instead. Availability still depends on the policy an enterprise has set.

Practical takeaway

Search saved prompts, CI jobs, and extension settings for the four retired ids and switch them to the suggested model, then confirm the enterprise policy actually exposes that model in the picker. There is nothing to uninstall. If a job still names Gemini 3.5 Flash, Gemini 3.6 Flash, Kimi K2.7 Code, or Claude Opus 4.7, GitHub’s position as of this changelog is that the model is already deprecated on every Copilot surface.