The OP is one cool customer! I think you can make the early flight unless something goes wrong. For myself, I would just spend too much of my valuable cruise time worrying about this--so for MY peace of mind, I would not do it. I acknowledge that this is more about what's in my head, but hey, it's my vacation. So, for example, last year we had a cruise arriving to Fort Lauderdale in the morning with a choice of a 10:30 am flight or a 6:30 pm flight (all the same day). I chose 6:30, we did the excursion to see the alligators, and still had a long afternoon at the airport. I would do it that way again. But, since the OP has got the early flights in the past and is cool with that--I say go for it!