Went to the registrar's.
I almost laughed when I walked in the door - alfa, the front desk was occupied by a 50-ish black woman.
She enrolled me in the lab section I want, since it opened between last night and this morning, and put me on the wait list, position #2, for the chem section.
I asked her what if the wait list never opens, she said sorry, you don't get in. Well, not a very good answer, but my impression was that she has very limited power. So hopefully I'll get in, but I'm not terribly optimistic.