Consider staying until 20, here's why:
If you were at 10 or even 15 yrs, I'd say punch, do AGR and apply to the Big 6. But at 17.5, you can stick it out for 2 more years, and then you'll have $50K+ per year for the rest of your life, for just fogging a mirror. My Tricare, for my whole family, is freakin' $47 a MONTH. You can't beat that anywhere. Airlines charge 4, 5, 600 a month for medical. Every month. My annual Tricare bill ain't $600...
13 months prior to retirement, drop your papers, set the earliest retirement date possible, and when you hit terminal leave, you can be in your airline class. I had a buddy that was flying for SWA while on Terminal leave! Once you have a retirement date set 12 mos out, the 365 boogey man can't get you.
It's a high performance problem to have; best of luck however it breaks for you.