lunch is available for those who board early.
We did a later boarding time for our cruise and something I didn't fully factor in was the stress of inching along in the long line of cars with everybody else trying to get there, park, and board, and you're just watching that clock tick, tick, tick with that warning that the ship will depart on time stuck in your head.
Ended up just fine, but I'd early board if I had it to do over.