Many factors could cause you to miss that flight...to many variables when the time is that close. Being a Crewmember for Princess I recommend that you book Flights in the afternoon...Anytime after 1pm would be safer.
The Diamond is a Beauty!! She was my first post in 2003 and home for me for 6mths on that ship cruising LA to Mexico every 7 days.
Happy Sailing!! you will love her.