Generally, the Adventure Guides will hold a Meet & Greet the morning (and usually into the afternoon) of the day the
ABD starts. So whenever you arrive, the hotel will let you know where the Guides are (or will be) and you can go meet them. If you don't make it to the Meet & Greet, then you will meet them at the Reception before the Welcome dinner that evening (or, for a few rare ABD's, the Welcome breakfast the next morning). When I've done a pre-day through ABD, I got a letter from the Guides the night before from the hotel introducing themselves and telling me when/where the Meet & Greet would be the first day.
The one exception to this that I encountered was the Arizona/Utah trip, which has a single transfer from the Phoenix airport to the ABD hotel in Sedona, so you meet the Adventure Guides when you arrive at the meeting spot at the airport. So I assume any of the few trips that have a single transfer would work that way.
The ABD Vacationistas *used* to tell you (if you asked) who were going to be your Adventure Guides once they were assigned (which isn't always that long before the trip). But occasionally, they would have to change the Guides for whatever reason, and apparently people would get upset because when they arrived, it wasn't the Guide(s) they were told. So officially, they don't do that anymore. Whether someone might tell you right before the trip or not I guess might depend on the Vacationista, but, again, I was told they weren't supposed to do that.
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