Hey all. Just saw this thread, I've been more of a lurker the past 12 months (Gardening finally!!!), but just so you know recons on USAA SL CAN BE DONE -- happened to me last February. For some reason though, you need to app VIA PHONE - upon approval, the rep can call UW who can manually up your CL if you request and your profile supports it. I went from $2k approval to $7k, boom, in 20 mins.
I highly suggest apping via phone -- once you app online it can not be done. You may want to app for a 2nd card (I did this an was fine) on the phone today and see what you get -- if approved for another $1k, ask them to request the CL higher for whatever purpose you need (BT is a great one), if the rep is pushy ask for a supervisor to do it. It can be done!!!! GOOD LUCK