Thanks for the follow-up. I actually knew about the difference in departures because our specialist explained them to me when we booked Belize. For our trip, AA is sort of an intermediary and then a company in Belize handles the logistics of the trip. We booked this itinerary because it is perfect for us and because our specialist told us that she had booked it many times before and could speak for its quality.
I looked into booking directly with some of the companies they work with because, at first, I did not understand the middle man either but could not find an identical itinerary or get the price point I was getting with AA so I went with them on it. If it all works out this summer, I will probably book Costa Rica with them because I like the itinerary better than ABDs. Now that will be a group trip (unlike Belize that's just our family) and they had some estimated dates for next year.
I agree this was VERY different to me at first and I thought we might be one and done with AA because I was so used to the ABD model but I have to say, I am looking forward to it being a bit more local with experts from the area. ABD has this, too, of course but I don't think it's quite to the extent of what our experience will be this summer.
That said, we have not experienced a trip yet so I may report back singing a different tune! We will see.
Also, I am planning to write up my experience in New Zealand and at Aulani (pre and post days to our ABD Australia trip). I will probably post it on the Aulani board since it's more relevant there. I will post the link here once I get done with it. Aulani is our new favorite place ever! We plan to go back next summer and every summer after that (just kidding) but after the big trip this year, we are going to stay closer to home for the next few years!