Long-Term Support for Enterprise Stability

GitHub has announced a new LTS program for GitHub Copilot models designed to give enterprises the time they need for internal security and safety reviews. Under this commitment, designated LTS models will remain available for a full 12 months from launch, providing organizations with a stable foundation for their AI-assisted development workflows.

GPT-5.3-Codex as First LTS Model

GPT-5.3-Codex, developed in partnership with OpenAI, is the inaugural LTS model. The model launched on February 5, 2026, and will remain available through February 4, 2027 for Copilot Business and Enterprise users. According to GitHub's internal data, GPT-5.3-Codex demonstrates a significantly high code survival rate among enterprise customers, indicating strong retention of generated code in production environments.

Model Rollout Timeline

GPT-5.3-Codex will replace GPT-4.1 as the default base model used when organizations haven't yet approved other models through their internal review process:

• March 18, 2026: Announcement of LTS and base model changes
• May 17, 2026: Automatic rollout of GPT-5.3-Codex as the base model for all Copilot Business and Enterprise organizations
• February 4, 2027: End of LTS availability window

Organizations have a 60-day grace period before automatic rollout. GPT-5.3-Codex carries a 1x premium request unit multiplier, while GPT-4.1 remains force-enabled at 0x for backward compatibility. GitHub encourages organizations to migrate to the latest models and offers account team support for those needing additional time.

Scope and Applicability

This LTS program applies exclusively to Copilot Business and Copilot Enterprise plans. Individual plans (Copilot Pro, Copilot Pro+, and Copilot Free) follow standard model deprecation timelines.