I used to be a boundary umpire. The rule is that from the time the umpire commences his approach to bounce no one is allowed to cross the centre square, in or out - regardless if there are too many or too few in the square.
I can't believe anyone would be looking to trade ANB. He's been here two seasons, absolutely been smashing the VFL and I don't see why he won't do the same in the big league in a season or two.