I can handle about 35 students in CS252. I have to give first chance to EECS grad students. If there is room left over, then may be able to add undergrads or grads from other departments.
If you are an undergraduatate, my only suggestion is to come to class for the first week or two to see what happens with enrollments. Also, CS 252 will be offered again next semester, so there may be room then.