<p>If the classes are full, GO THE FIRST DAY no matter what. If anyone doesn’t show up, they are supposed to be dropped (I say supposed, because some professors don’t drop students, instead relying on the students to drop themselves). </p>
<p>Some programs are nice enough to sort of allow “dibs” on any open seats to those that show up the first day (I’ve had multiple classes do this, actually), where showing up the first day got you a spot in the class anyway. I’ve even had classes that had more people show up than there were seats that allowed everyone that showed up to be added (although I believe that this is up to the professor teaching). </p>
<p>Since you’re apparently a meteorology major (judging by your post history), I wish you luck, especially if you’re trying to get into MET2101/2700. For some reason they cut the number of seats in those classes significantly right after fall registration closed initially back in April.</p>