it's not a loophole. You just have to provide justification WHY you want to separate with less than 180 days notice, and your SQ/CC or WG/CC has to buy it. In my case, I just put that I had multiple employment opportunities on the shortened timeline, and mine was approved (128 days notice from application submission to DOS). Took AFPC 4 weeks to approve my app, and I went on terminal leave 35 days later. Since I was applying with the justification of being a free agent (ADSC expired), they weren't going to disapprove it...(I think the only time that could happen would be stop loss).
Took TAP while still waiting for app to be approved, since you can take it up to 2 years out from your expected DOS, and a nice A1C from the MPS went ahead and loaded an outprocessing checklist for my in vMPF so I could get ahead of the game, since it was going to be such a short period between notification and terminal leave (I had 60 days terminal).