Marriott transfers to AA, last I checked, take 2+ days, so that's one instance where the 5-day hold could be useful. Bilt transfers are instant, but not sure that many folks have significant stockpiles of Bilt points (I use it for 2x points on Lyft , on top of the 10x points I earn with CSR, but don't have the credit card). And being awash in AA points is a good place to be, Mr. BoH. I also have plenty, but as others above mentioned, it's much easier to let a hold expire (or cancel it) than to actually book and then cancel and then have to message or call to get miles redeposited (it randomly won't refund miles automatically for me, probably 10% of the time, and never if the trip is close at hand).