I think the "after delivery" refers to the "reverse the purchase," not to the "cancel" part. That "or" in between implies, to me, cancel before purchase or reverse the purchase after delivery... I am hoping not to find out exactly what is meant!
For now, I've done the FUSC charger through the app, and I have *not* submitted the form for the FSD transfer. Since I don't have a VIN, let alone an EDD yet, my thinking is that if I need to cancel the order, at least that will be one less thing to roll back. But, fingers crossed that I get a VIN and EDD and actual delivery prior to 3/31/24.