30
ctd57:
For the USAF, USAFR, and ANG, it is 30...I'm pretty sure this is Federal law/Title 10-driven, meaning the other military branches are the same.
This means you can start UPT and turn 30 the next day. Exceptions are rare--I had a student about 4 years ago who was 29 and 8 months...he had orders in-hand, but a month before he was to start, his wife got cancer. He delayed his start by 6 months while she was treated (and eventually recovered), so he was actually over 30 on day-one of UPT.
Waivers are tough, although sometimes the Guard can get them. The unit either has to want you really badly, or you have to possess some incredible political connections, like your Dad plays golf with the State Adjutant General.
I don't think your previous Naval time will count.