If I prepay for a room while booking online will I still be able to upgrade room at checkin? Either by luck of platinum status, or pay myself?
I don't see why not if an upgrade is available.
I agree with IAHFLYR. Depending where you are, I've had good luck calling the hotel reservation directly, the day before you arrive (if you haven't already been notified of an upgrade), mentioning you're a platinum member, and asking if they possibly have any upgrades available for your arrival the next day. I've always found that being really nice to them on the phone works well, most of the time. Good luck!
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