That’s been questioned a lot and of course nobody knows but I personally feel like messing with the # of people in a BG and the # of BGs and then managing how to call back said BGs is just way too many variables and way too complex.
I could be way wrong but I see no reason for them to mess with the # of people in a BG. Keep that standard, determine how many BGs you want to issue for the day, and then call them back while monitoring the throughput of the ride.
I mean this is Disney IT. How many variables are they really capable of handling here