Originally Posted by
tarheelnj
Forgive the technical ignorance....
If you have been issued a mobile key, then have you effectively taken occupancy of your room? Presumably the mobile key wouldn't be effective until the previous occupant has left, but in the case of a suite it could very well have been vacant the night before. Can the FD clerk tell when you've used the mobile key for the first time? It's been said several times in this thread that you aren't really upgraded until you have your key in hand. This could be the electronic equivalent of the hotel clerk heading you off on the way to your suite after checking in, taking your physical key from you, and handing you a key to a regular room. Or, stated differently (not to get pedantic), when is the property's last chance to downgrade you?
If you have a mobile key, the previous occupant's key no longer works and housekeeping has turned over the room.
The property is very unlikely to downgrade you at that point because you had access to the room (they don't know if you're on-site or still on a plane) and giving it to someone else means they'd have to get it checked by housekeeping (they wouldn't know if you had dirtied it without checking access logs, so probably easier to send housekeeping) and change keys... possible but unlikely.
I would say, they can downgrade you from a complimentary upgrade without needing to offer compensation up to the point you've entered the room. Asking you to change rooms after you step foot inside would impede the hotel night you booked. But practically speaking, they almost will never downgrade you from the point you already have a (mobile or physical) key.