You don't have to request it, you just keep your bags in your room and then gather in the lobby around 7-7:30 and walk off with all your stuff.
Make sure you keep track of ferry times, this season has been variable with suddenly cancelling times or filling up others. My uncle (lives on the Island) has been stuck overnight on the mainland and needed to get an emergency hotel when they cancelled their last sailing of the day. (Or he's had to drive to the north end of the island to catch an early morning ferry from the other terminal to make a dr's appt.)