I don't know anything about the riverboat finale, but that sounds like a really stupid and unnecessary thing to do. And if they significantly reduce the AA's, especially to THAT degree, then we've got a serious problem and the ride is destined to be a disaster. I'll reiterate that what I was told seemingly contradicts the reduction claim, at least regarding the overall amount included in the ride. In particular, someone here said none of the old AA's were being kept and would all be scrapped. Whereas I was told the AS figures would be repurposed for the new ride.
Unless they've somehow come to the strange decision to increase the amount of AA's in the other scenes but reduce the amount in the finale. Which wouldn't be a good idea either. The finale scene is the largest room in the ride by far and the place you'd expect to see the most figures. It would feel exceptionally empty with such a piddling amount of figures. The other rooms have much more limited space, so I can't imagine there would be much room to substantially increase the amount of figures.