You might want to edit again.

How is he coping with the pregnancy, sometimes the issue is plain old kids issues with the added complication of giftedness.

There are a lot of changes going on for DS. I'm also in the camp of not punishing - nit for stuff that appears to be either due to settling in or developmental.
I agree that there could be some pigeonholing going on. Maybe there is room for building a relationship with the teacher and offering reminders that you view DS as 6 and expect his behaviour to match his age.