I'm currently seeing this error:

It seems like the default model selection (gpt-4o-2024-11-20) is the culprit and is no longer in the list of models returned by CopilotChatModels:

(Note that I generally don't check the chat models so I'm not actually sure if "gpt-4o-2024-11-20" was in the list before)

Setting the correct value, gpt-4o, in the config is my current workaround