[BUG] Windows app update v1.11187.4 silently changed Cowork space model from Sonnet 4.6 to Opus 4.7, model selector now greyed out

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

What happened:
After updating to v1.11187.4 and restarting, my Cowork space model was silently changed from Sonnet 4.6 to Opus 4.7. The model selector in the chat is now greyed out and locked — I cannot change it back.

What Should Happen?

What I expected:
The update should not change the model without user consent. The model selector should remain functional.

Error Messages/Logs

Steps to Reproduce

Steps to reproduce:
Have a Cowork space running on Sonnet 4.6 (migrated from a Chat Projects space)
Update Windows app to v1.11187.4 and restart
Open the Cowork space — model is now Opus 4.7 with selector greyed out

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

1.8555.0

Claude Code Version

1.11187.4

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Other

Additional Information

This space was migrated from a Chat Projects space. At migration time the app stated the space would be locked to the legacy model — so model changes were explicitly flagged as restricted. The update appears to have overridden this without warning.