Yep, if you *might* need it earlier, book for earlier. No need to try and play the usual game of "book 60 mins later than planned and get an extra 60 minus on the rental" (where large airports pre-print contracts, they often print them hours early and you can get a free hour or two as they don't time-stamp the pickup if you don't swap cars, use the app to get a QR code to exit the lot, etc). They don't pre-print in AK so they'll stamp it with the minute you are at the counter.