The cat cruise boards at 3:30 and gets back around 5:30 this time of the year. I really doubt that you will make the Saturday cruise. Do sign up for your reservations just after you check in at the resort. The cat cruise is popular and can fill up early in the week.
I think it's only a few days each week but they have 2 different crews and times or they did when we went at least. One is the sunset cruise and the other I think goes out earlier that day. I wouldn't go the day you get there. I'd check out the resort and relax.
I don't think the Cat Cruise runs at CSA on Saturdays (I think it was Mon/Wed/Fri when we were there last September), so that'll take the first-day worry off your mind.
I would recommend that, once you've checked in, you get signed up with for the next available cruise (call the front desk) as early as possible. I know they all filled up the week we were there. Don't wait until the morning of the last day available or you might be disappointed!
I think that I read that it leaves about 3:00 or 3:30 ending around 6:30 so if your landing at 1:30, I don't think you'll make that with the 1 1/2 hour ride to CSA and check-in. Plus I think you have to sign up/reserve about a day in advance anyway....at least from what I've read on these most helpful boards. Come April 3rd, I'll be able to tell you for sure as that's when we're there.
Honestly, I don't think you'll make it. I seem to remember it leaving at 4-430 ish? Even if you are at the resort and checked in and can make the boat, it would probably be all booked by that time. There are limited "seats" and I seem to remember it's one that does fill up.
The Cat Cruise leaves at 3:30, you board at 3:15, and you need to reserve your spot ahead of time, so it won't be possible to take the cruise your first day there if your flight doesn't arrive at MoBay until 1:30. Just reserve another day!
You won't make the cat cruise on your first day. It leaves around 3:00/3:30p (and comes back at sunset). If you don't land at MBJ until 1:30, by the time you go through immigration, customs and drive to the resort, you won't be checking in until around 3:30p. But when you arrive, you can sign-up for the next cat cruise.