honestly, if i was in your situation....i would go to the IRD where i knew the most people.
i would want to see as many of my closest sisters as possible, so whether that's UAB or brenau is your decision. reunion day is all about meeting up with old sisters and seeing what your chapter is up to today...so go with whichever one you know you will have the best time re-hashing old sorority behavior.
have fun wherever you decide to go!!!!!!!
liep,
monica