New articles of impeachment from the House in 3...2...1...
If it happens at all, I don't see it happening before the election. And that brings me to a technical point, which I have mentioned before:
Suppose Trump wins reelection, and the House votes early in his second term to impeach him for something he did during his first term. Can they do that? In his second term, he is ... well, he's in his second term. Can a President be impeached essentially after he has left office? I can see his defense coming down to, "I didn't do that. That was the former President Trump. I'm the second President Trump."