I've flown 'em nonstop to SAT before out of ATL, but it seems to be one of those spaghetti-against-the-wall destinations that's now-you-see-it-now-you-don't. When they do have it, it's probably not daily. Would second the advice about not booking anything non-refundable 'til a month or so out (and try to favor free-cancellable things even then).