You can check in early. The question is whether or not your room will be ready. It might or might not be. When you check in, if they tell you it's not ready, ask if there is any other room ready that you can take. There might be something available. If nothing is, they'll hold your bags at Bell Services so you can do something else. If you bring your swimsuits in a carry on, you can go swimming at the resort while you wait. They have towel service at most of the pools, so no need to bring those. Or you can hit the parks.