GitHub Copilot: MAI-Code-1-Flash Reaches All 8 Surfaces; Opus 4.6 (fast) Sunsets June 29

TL;DR: MAI-Code-1-Flash, Microsoft's small coding model for Copilot, now runs across all 8 surfaces including CLI and JetBrains; Opus 4.6 (fast) leaves GitHub Copilot on June 29 — switch now.

Two GitHub Copilot model changes from June 18:

MAI-Code-1-Flash on 8 surfaces. Microsoft's purpose-built small coding model has expanded to all major Copilot touchpoints: CLI, Copilot app, GitHub Chat, Visual Studio, GitHub Mobile, JetBrains, Eclipse, and Xcode. Available on Free through Max plans (Business/Enterprise soon). MAI-Code-1-Flash is designed for low-latency completions on shorter tasks — the fast pick for JetBrains inline completions and CLI interactions while Claude handles heavier agentic work in a separate session.

Opus 4.6 (fast) deprecated June 29. GitHub Copilot is removing Opus 4.6 (fast) from all Copilot experiences on June 29. If you or your team have it pinned in any surface, switch to Opus 4.8 or Sonnet 4.6 before month-end to avoid a hard cutover.

Why it matters: Knowing what model powers each Copilot surface matters for budget and quality decisions — especially on usage-based plans. The Opus 4.6 (fast) cutover is a hard date, not a gradual sunset.

Sources: MAI-Code-1-Flash on more Copilot surfaces — GitHub Changelog (June 18), Opus 4.6 (fast) deprecation — GitHub Changelog (June 18)