Just to add a data point for everyone.
As everyone has eluded too so far, you board the blue Alamo bus and let them know you're part of the emerald club. They will radio ahead as they have your name on a sheet to get the contract ready for you.
I arrived quite late (9pm Feb 20th) No many cars lef, booked a fullsize and got a fullsize. I asked about other vehicles but the employees polite'y let me know that they are still shor 3-4 cars. so they didn't haev any wiggle room.
Ended up with a Chevy Malibu with a sunroom, the other option was a Nissan Altima with no sunroof.

The staff were all really nice and helpful as stated as above. Very very small lot but that's because the national side is closed and enterprise is operating by itself on the other side.
Willing to come back again!