KBab,
I'd make sure you make it to the Societies Fayre, as the UAS i joined only took applications at Fayres for 2 days per university. I phoned during the summer, trying to get a head-start, but they weren't having any of it, and just told me to see them at the fayre.
Get ready for a hard slog though. My university's Societies Fayre was on Sep 22nd, and we were formally enrolled on Nov 10th!!