GVT Verandah Rooms

Just changed my reservation to a GVT Verandah room & am wondering when they assign an actual room number? When do you find out what that is? Do they tell you ahead of time or when you check in? Are you able to adjust that at the port if you are looking for a room on a higher deck or in the aft of the ship?

You’ll be assigned the room number shortly before departure. You can’t change it from what I’ve read. But you may end up being assigned a higher category (upgrade.)