The model is live everywhere Copilot runs: VS Code, Visual Studio, the Copilot CLI, the cloud agent, github.com, GitHub Mobile, JetBrains, Xcode, and Eclipse. GitHub points to better complex problem-solving and large-codebase navigation as the reasons to reach for it over the existing roster. Business and Enterprise admins won't see it until they flip on the Claude Opus 4.8 policy in Copilot settings, so it isn't automatically in front of everyone on day one. The catch is the meter. Each request carries a 15X premium multiplier until June 1, when usage-based billing kicks in — so a heavy week against Opus 4.8 will burn through premium allowance fast. Worth deciding before then whether this is your daily driver or the model you save for the gnarly stuff.