I dont think anyone has done that, that has posted here about it. What SHOULD happen is, you would be charged for the difference between "what FSD cost if you own EAP" and "what FSD costs if you dont have EAP". It likely would be looked at like you were trying to game the system, so I would expect that they would just charge your card on file the difference.
Either that, or they wouldnt let you refund the EAP at all, or order the FSD until after the return period for EAP passes. One of those things is most likely to happen.
