Depends on the university policy. To me, I don't see any difference between certain AI use and plagiarism. And plagiarism ought to result in expulsion.
As an instructor, however, it is increasingly difficult being 100% certain someone is using an LLM. While the easy spot is usually shorter paragraphs and a final hedging paragraph (the one paragraph that OpenAI included so they won't be liable if shit goes south), there is still no way to be sure.
So instead, I just have to begrudgingly nod along as my engineering students dump awful, boring AI texts on me.