Welcome to Cruise-Chat. My wife and I always fly in a day before our cruise. We usually board between 11:30AM and 12:30PM. Your luggage will be taken to your cabin, so you should only be carrying your carry-on luggage. We alway head straight to the Windjammer for a great lunch. You should be able to drop off your carry-on luggage in you cabin. It usually says the cabins aren't ready until 1:00PM, but we do it. The Explorer is a awesome ship. Don't miss the ice show!