According to milrecruiter, it is this: minimum PCSM score of 90, no exceptions to policy, and willing to fly any AFRC tanker or transport aircraft at any AFRC location. Unsponsored candidates are not eligible for fighter, bomber, or special-mission aircraft.

Would have to confer with your recruiter just in case.

I just applied to the last board in October as an unsponsored candidate, still waiting for those results. But my recruiter said I had to wait until after potential selection by the board to go get my FC1, but maybe that varies case by case. All I had to do was MEPS and all the paperwork.