They wouldn't just impose it instantly. There would clearly be a grace period. Otherwise the PFA would have something to say I'm sure as well.
You would like to think so but we are talking about Bin Hammam - the pronouncement a couple of months ago from the AFC made no allowance for a grace period.
To me there is little or no down side to waiting for certainty about the rules past next season but huge risk if we don't and then find we have used up our available import spots for "development players".