AF Soar,
Yes... you can find active duty orders to finish out your 20. It will be very very difficult. Any unit that will take an O-5 is going to be looking at you with the big eye and wanting to know the story up front, that being said, many units need that upper middle management type if you are willing to do those jobs. The AF is in a bit of a pilot shortage you know.
If you have some buds that can bring you in a unit and promise you a steady state of orders, then that is one thing. Understand this, straight from many Generals mouths in AFRC, "AFRC is not in the business of giving active duty retirements" (of course these same Generals all have their active duty retirements, brilliantly played)...not that it does not happen in todays AFRC. It is more and more uncommon. In the Navy, it is now impossible. Many Navy dudes crossover to tag a few more years of active duty and finish up. Again, rare and they knew someone or the units where dying for people..i.e reapers a few years back.
If you punch at 17.5 and all the sudden the rules change in AFRC to not let folks on orders after the 18 year point, how disappointed will you be..only you can answer this. It has not happened yet, but the stopping of orders after 18 years could happen at any moment. Congress, budget cuts, continuing resolutions, ugh, it is never ending when you are looking for orders and it is a new game every fiscal year. Can you get to the finish line and be a good employee to your new employer, yes, you are 38, you have 12+ years to get 2.5 years. That is pretty easy. I know a few jobs in AFRC that are looking for good help and have an endless supply of money, that being said, you have a bird in the hand right now. PM me and I can give you contacts if you wish to talk with them. If it where me, I would stay and focus on enjoying the last few years, fly as much as possible and prepare for your next run. Being a reservist and doing two jobs does have its drawbacks. Active duty is pretty easy, even with deploying, not like you need to worry about promotion and the silliness now that you know it ends at 20.