GitHub Copilot has become an indispensable companion for many developers, promising to elevate productivity and streamline coding workflows. Yet, a recent community discussion on GitHub, initiated by user dddyfx, has brought to light a perplexing issue: users attempting to select advanced AI models like Opus 4.5 or 4.6 find their requests silently defaulting to Sonnet 4.5. This behavior isn't just a minor annoyance; it sparks critical questions within the developer community about control over AI models and its direct impact on development performance.