Where did _that_ come from?

Apparently, I just got a GI Bill payment direct-deposited in my account yesterday. A 400-bucks-larger-than-usual one, at that. Which is odd since I'm not taking courses over the summer, nor have I clicked on the "Verify enrollment" page which would attest that I had. Now, I'd be happy to keep the money, but I somehow think this is a mistake, and if it doesn't get corrected now, they'll take it back just when I would have needed the cash most. As has happened to me before. Twice. So I should probably call them first thing Monday morning. No rest for the wicked, or something. :-P