Here is what you can do to get out of the regular AF absent Palace Chase. Twice Failed of Selection (2x FOS) to the next higher rank requires, by law, that the officer be separated (unless continuation is offered and accepted). ADSC is a service-level regulation and the law trumps ADSC.
1. Write a Do Not Promote me letter to the promotion board. If you do this for your APZ board, this will get your separation pay revoked, but since it's an advance on retirement pay and you intend to get a Reserve Retirement, it doesn't much matter. The law also stipulates no separation pay for an eventual separation for writing a do not promote me letter to your IPZ board, but I don't know if the AF tracks this.
2. If you make the promotion list anyway, decline the promotion.
3. If you are offered continuation upon your 2nd FOS, decline it. You won't get separation pay in this event.
Doing the above will get you once failed of selection, so you'll need to fail selection a second time to get your date of separation which is normally 6 months after the public release of the selection list. You can move this to sooner, but due to bureaucratic processes any sooner than 2 months after the public release is probably too soon. You'll need to get on the scroll to get a reserve commission and that won't happen until you get a waiver. Even after you get a waiver, the scroll process can take two months. Getting on the scroll before separation will enable you to Palace Front.
Since 2x FOS disqualifies you for a reserve commission, you'll need a request for waiver signed by your losing wing commander and gaining wing commander to go to the ARC, so hopefully you can do the above without burning any bridges. Since the ARC needs people these days, it shouldn't be much of a problem as long as you have a good relationship with your command. As long as you don't have a break in service between the regular AF and the ARC (i.e. you Palace Fronted), you'll meet a promotion board in the CY after your separation and probably be promoted provided you have your PME done and don't have any adverse indicators.
You can also avoid having a break in service by being placed in the IRR, but this rarely happens. Many involuntarily separated officers are not placed in the IRR due to bureaucratic ineptitude. Regardless, the scroll process is required to get your reserve commission and without doing that, AFPC *will* give you a break in service and then *may* place you in the IRR. The end result is that you will meet a promotion board in the 2nd CY after your separation instead of the 1st. It's much better to go to the SELRES or ANG via Palace Front than to try to get a scroll done for the IRR. I don't know if it can be done because the gaining wing commander equivalent in the IRR may not cooperate to sign the request for waiver. From everything I've seen, the Air Force has very little interest in properly managing IRR officers. I say all this because by virtue of receiving separation pay, the law requires an officer to serve in the IRR for 3 years, but many are not placed in the IRR or are not scrolled and therefore have a break in service.
Any unearned portion of a bonus already paid will be recouped. It is within their right to recoup a portion of any tuition assistance paid, but not "earned" because you didn't fulfill the ADSC, but I haven't seen this happen except for voluntary separation programs. As far as transfer of education benefits with the GI Bill, it is within their rights to revoke the benefit, but if this happens you can reinstate it in the ARC. Contrary to popular belief, there is no continuation that is forced on an officer--it is offered and then the officer either accepts or declines regardless of ADSC.
sources: AFI 36-2501, AFI 36-3207, 10 U.S. Code § 1174