We went on the Pride back in June and I did not see anybody getting early check in. If you take the bus a porter pulls your bags off the bus and all you do is identify them when you get off and the next time you see them is outside your room later in the day. As far as checking in we checked in about 10am and the ship did not start boarding until about 1:30. Check in was quick and easy and took only about 10 minutes and is done on the Queen Mary. I had a suite so we had VIP priviledges which only meant when they started to board we were the first on.
I take it your going on the Pride which was a awesome cruise for our first time. I will be on the Spirit Dec 18th. Have a good trip !