There won't be very many gaps for the kids who have been forced to move out, to be able to move into tho. Which is a real shame. Maybe actually makes sense to disband the Family Section so that current families in there can continue to sit next to each other, irrespective of age. And the JCVLs on the waiting list can just, er, WAIT.
Exactly the reason I didn't get season tickets in the family section as there was (when the amex opened) / is no policy on where you go when your children grow up apart from onto the waiting list. You should be allowed to stay on in the family stand until a suitable space opens up in another area of the ground where you take priority over the waiting list. Its not difficult to come up with a simple solution that doesn't piss people off.