I have an upcoming reservation that I called Marriott to use the RC Card club level certificate for. They are confirming that the certificate has been attached to my reservation but the room type on the reservation does not say Club Room. They insist all is okay and the hotel will know its a club room. Is that how the certificate upgrades are processed? I fear this is going to be an issue at check in but Marriott reservations says its all good.
When I have used them, the room type changes to a club level room. Honestly though, as long as the rate says club upgrade you're probably fine. These certificates are not held by a large number of users so there's a lot of bugs and problems that Marriott is just never going to fix. For example, even when they attach certs the reservation tends to still say you need to attach certificates, and you just have to ignore the message.