I totally agree with Sandy. We always travel the day before. One time a piece of our luggage got lost. If we hadn't arrived a day early, we would have had a big problem. As it was, the luggage arrived the next morning and we were good to go.
By arriving a day early, you can also relax, get a good night's sleep, and be onboard the ship by lunch time. Every extra hour on the ship is a bonus!