Here's an interesting question (at least to me):

Say I'm flying a transcon, maybe EWR-SFO and back, and want to use miles to UG. Let's say that it's F0 until day of departure, but then there's 5 F seats released. Would I, wanting to UG with miles, get the F seat ahead of a Platinum or other elite trying to UG with status? What if I'm a Silver or Gold and there's 10 Plats on the waiting list for 5 seats?