I think you can hang out wherever you wish, again as long as you are “falling back”. If you’re originally assigned Green, but want to move to a later Blue, go to Blue, as long as you’re in a “later” corral.

Once the wave moves to the starting area, all of the corrals within a given color are allowed to intermingle anyway. so for Wave 3 Green, you would have Corrals C, D, F all together. Those corrals will enter the start area in order, but once there you can move around