Custom assistant model selection not working

No matter which model I select, it goes back to GPT4.

It's supposed to be the model I select.

Custom Assistant won't let me switch to Claude Sonnet 3.5 and keeps reverting to GPT 4.

Custom Assistant should remember the model I choose.

Hiya! Sorry for that regression, we have a hotfix on the way out that should be live in ~1hr.