Sessions: Model choice changes when new session starts

[bamurtaugh]

• Kick off a session with model A (in my case, Opus 4.6)

• Session starts
• ❓ Session is now using model B (in my case, gpt-5.4, which I didn't switch to at any point)

This doesn't seem to happen if it's an existing session (model choice is preserved when sending messages in existing sessions).

[sandy081]

@bamurtaugh I am not able to reproduce this - can you please provide the exact steps?

[bamurtaugh]

@sandy081 here's a video, following the same steps I took above:

Model.Change.3-26.mp4

It seems this only happens sometimes, and I can't quite determine why. If I send a new message to a repo I've already interacted with after this latest VS Code update and that I've already changed the model on before, the model choice seems to remain consistent. So perhaps this is just a one-time side effect at this point in time after the latest update?

[bamurtaugh]

In the latest Insiders, I just experienced a different version of this, with a different second model (so it doesn't always switch to gpt-5.4, as it did in both cases above from yesterday), and then switching to a third model:

• I have Opus 4.6 selected for a new CLI session
• Started the session
• Model switched to 4.6 once session started working
• Once session completed and produced changes, it switched again to gpt-5.4