Wow, that's really weird. Two weeks ago I bought two ATBs at a show, supposed to be females but, of course, when I had them probed, males.
One liked to stay in the water dish and I thought that was pretty odd. Turned out it had mites. My friend bought a bunch of snakes off the same person I got the ATB with mites from and all of them had mites too!
I'm not saying yours has mites, you'd have noticed it by now.
I'm just getting into ATBS and have 3.1 AARGH, and I'm reading everything I can on them so keep posting as to what happens w/the one the blisters.