Daily · · Copilot · 🌶️🌶️Medium: worth a look this week Why: Models deprecated Oct 19
Six Copilot models just left the picker
Action needed: six Copilot models were deprecated on Oct 19, 2026, including GPT-5.5, GPT-5.4 and Grok 4.5. Move workflows and integrations to the suggested alternatives, such as GPT-6.1 Sol, GPT-6 Luna, Gemini 3.8 Flash and Grok 4.7.
In plain English
If a workflow still names one of these models, it needs a supported one.
GitHub announced these deprecations on Sep 18, 2026. They cover most Copilot experiences, including Copilot Chat, inline edits, ask and agent modes, and code completions. The suggested alternatives:
- Gemini 3.7 Flash → Gemini 3.8 Flash
- GPT-5.5 → GPT-6.1 Sol
- GPT-5.4 → GPT-6.1 Sol
- GPT-5.4 mini → GPT-6 Luna
- GPT-5 mini → GPT-6 Luna
- Grok 4.5 → Grok 4.7
What to do
- Update workflows and integrations to use supported models.
- Copilot Enterprise admins may need to enable the alternatives through the model policies in Copilot settings. Once the policy is on for a model, it shows up in the Copilot Chat model selector in VS Code and on github.com.
- You don’t need to remove the deprecated models yourself.