Originally Posted by bdemaria

The elite room guarantee is a good news/bad news benefit. Indeed you can get a room at a sold out property, but the prices are usually quite high. You won't be able to convert the current reservation to a lower rate. Properties know this benefit could cost them dearly, since - by accepting your reservation at a fully booked property - they know they may have to 'walk' another guest to another property.

IME, people book well in advance for conventions & properties block lots of rooms to accommodate the convention, then close to the actual event, people cancel, etc... so I would keep the current, pricey room and continue to monitor availability, etc.. to see if prices drop/regular rooms open up. If they don't, then you can choose to pay the guaranteed rate, or cancel the room the stay further afield.