I figure that each hotel prints out a list of all guests and on this list the status is mentioned. What I am wondering is whether if you are Gold when you book a room but become a Diamond before you check in for that room if your status will show as Gold or Diamond. I know that it works this way for some airlines.

For some of my reservations (which I always book online) I've written "HH Gold" in the comments box. I assume this will still appear to the hotels, but will my new status show up too and override it?