On 16 November 2026 GitHub will remove four AI models from every Copilot experience – including Chat, inline edits, ask, agent modes, and code completions. The affected models are Claude Opus 4.8, Claude Opus 5, GPT‑5.6, and GPT‑6.1. For most customers the platform will automatically enable the suggested replacements: Claude Opus 5.5 for the two Opus models, Terra for GPT‑5.6, and Sol or GPT‑6 Luna for GPT‑6.1. Individual subscribers on annual plans retain access to Claude Opus 4.8, so the change does not affect them.
Copilot model deprecation details
The deprecation applies uniformly across all Copilot touch‑points. Under the default configuration, Enterprise and Business tenants receive the alternative models without manual intervention, unless an administrator has disabled the global default or explicitly turned off a specific model. In those cases the admin must enable the new model through the Copilot settings’ model policies, after which the model appears in the Chat model selector.
Configuration and policy implications
- Model policies: Review the global default flag in Copilot settings. If it has been overridden, add the replacement model (
Claude Opus 5.5,Terra,Sol/GPT‑6 Luna) to the allowed list. - Automation scripts: Any CI/CD step, API call, or custom integration that pins a deprecated model name must be updated to reference the new model identifier.
- User experience: End users will see the new model in the selector after it is enabled; no manual removal of the old model is required.
Operational considerations
Switching models can affect prompt phrasing, token limits, and response characteristics. Teams should schedule a short validation window before the deprecation date to run representative workloads against the replacement models and capture any regressions. Because the change is transparent for default‑enabled tenants, the primary risk is a mis‑configured policy that leaves a workflow pointing at a now‑unavailable model, resulting in failed completions or API errors.
Related CloudNinjas coverage: AI engineering.
What This Means For Practitioners
Action items for AI, cloud, DevOps, and security engineers:
- Audit all Copilot configurations – UI settings, policy files, and automation scripts – for hard‑coded references to the four deprecated models.
- If you manage a Copilot Enterprise or Business tenant, confirm that the global default is active or manually enable the suggested alternatives in the model policy panel.
- Run a smoke test against the new models in a staging environment before 16 Nov 2026 to verify that prompts, token usage, and integration points behave as expected.
- Document the change in your team’s operational runbooks and update any incident response playbooks that reference model‑specific behavior.
- For individual annual subscribers, note that
Claude Opus 4.8remains available; no action is required.
Monitoring the Copilot settings UI and staying aware of any further model announcements will help avoid surprise disruptions after the deprecation window closes.
