Thanks guys, I really appreciate the feedback. We're still waiting to hear more from the principal but I'll look into contacting my congressman and be ready to do so. I also might be able to get more info from the district's lawyer directly.

The interim fix is splitting days, having her sit in with 1st grade in the morning and then going to her current K class in the afternoon. It's better than nothing, but I worry that it might draw more (potentially negative) attention from her 1st grade classmates. I was hoping for the transition to be as 'normal' as possible. I'll update when I hear something.