GitHub has moved local Copilot sandboxes from preview to GA. Enterprises can now combine centrally managed approval policies with operating-system-enforced limits on what coding agents can actually reach.
The useful boundary change is that Copilot can now cross from code and terminals into ordinary desktop interfaces, with per-app approval and organisation-level controls.
The useful part is not the 800,000-line headline. GitHub has published unusually detailed receipts for a production-scale agent-assisted migration: roughly $120,000 of token spend, 14.5 weeks of incremental releases, dozens of regressions, extensive compatibility tests and a workload-specific jump from 7.55 to 120 session lifecycles per second.
The material change is that model routing is no longer a single opaque optimization target. Developers can now tell Copilot whether to bias Auto toward lower cost, a middle ground or higher quality while GitHub still chooses a model prompt by prompt.
The technical-preview feature separates Copilot CLI from GitHub Cloud for core coding, shell and repository workflows, giving regulated and isolated environments a supported agent path while leaving cloud-dependent capabilities such as GitHub-hosted model selection and web search unavailable.
Copilot code review now moves from advisory assessment toward a governed merge gate. The public preview remains off by default, and GitHub’s current docs let administrators separate AI approval itself from whether that approval counts toward required-review policy.
From September and October, Copilot Business and Enterprise seat access becomes more tightly coupled to upfront payment. A separate September 28 policy migration enables a unified Copilot experience by default, retains github.com chat data for the life of the account and changes code review’s default effort from Lite to Balanced.
GitHub Copilot can now turn Slack or Teams threads into collaborative cloud-agent sessions. Teammates can add context and steer the work in public, while repository permissions, agent budgets and optional extra PR approvals remain the main control boundaries.
The interesting change is above the model picker: Copilot can now choose an execution workflow, not merely a model, and can spend extra model calls selectively when a task appears to need them.
The corrected rollout matters for supply-chain configuration: teams can still remove PATs for qualifying GitHub Packages, but GitHub changed the precedence model after some npm update jobs were mistakenly routed through GitHub Packages.
Stacked pull requests are now generally available on GitHub. The shift matters as coding agents make large changes faster than humans can safely review them: teams can keep one coherent change dependency-ordered while reviewing it as smaller PRs.
GitHub’s credential-response story now has both discovery and containment: enterprise owners can export SSH keys, PATs, OAuth and GitHub App tokens with ownership, scope and last-use metadata, then use selective revocation rather than invalidating every credential a user holds.
GitHub Actions now has enforceable actor and event rules before a workflow starts, plus a coming default block for a trigger that can expose repository secrets to untrusted fork code.
GitHub-hosted Actions jobs that use `ubuntu-latest` are about to change operating-system generation without a YAML edit; teams can test on `ubuntu-26.04` now or pin 24.04 while they migrate.
The scanner itself is not the new part. The September 16 change removes the CodeQL-default-setup gate that GitHub’s July rollout originally required, making AI-assisted vulnerability detection easier to add to repositories with different code-scanning configurations.
The deadline is no longer theoretical: browsers, Git HTTPS backends and API clients that still depend on SHA-1-era TLS algorithms can now lose connectivity to GitHub.com.
GitHub Spark stops being available to existing users on August 31, 2026. Deployed apps are meant to keep running, but owners should export code to a repository now; Spark apps using `llm()` need a separate inference provider because the underlying GitHub Models service retired July 30.
The change turns cache poisoning from mostly a workflow-design warning into an enforceable permission boundary. Teams can let untrusted jobs restore caches without writing them, prevent reusable workflows from escalating cache access and isolate jobs that only need to publish cache entries.
The useful change is where enforcement happens. Teams can now make unresolved leaked credentials a branch-policy failure, with organization and enterprise rollout plus API configuration for large repository fleets.
Teams with pinned, custom-image or auto-update-disabled GitHub Actions runners can now see registration or job execution fail before the September 25 cutoff. The migration is not just a one-time jump to v2.329.0: already-registered runners must also stay within 30 days of the latest runner release.