I transplant from rooters to a 1/2 gallon pot as soon as I see roots coming out of the rapid rooter plugs. They then stay in that half gallon pot until I know which are females, then I transplant the females to their final pot, usually a 4-gallon square pot.

So, if you see roots coming out of your plugs, get 'em into a pot of some kind. Those plugs aren't designed for them to be used for weeks, just long enough to get a small root system going.