Transplanting/flowering question...HELP

So I am growing 8 plants for personal use in a closet. The plants are almost a month old and getting pretty big. A few of them ar in pots big enough for the entire grow cycle but a couple of the other ones are in smaller pots. Yesterday I noticed that some of the roots are coming out from the holes on the bottom of the pots. Here is my dilemna......With the limited space I cant transplant the ones in smaller pots to bigger pots. I figured I could wait until I flower (a week or so) and then when I can tell males from females, throw out the males and then transplant the females in smaller pots because I will have added space to work with...

Is this a bad idea transplating so early on in flowering stage?
Also is the problem witht he roots showing from the bottom of the pot bad? Possibly stunt their growth? Thx

1. The roots will eventually become root bound in the smaller pots. That's bad.

2. Yes, you can transplant after the plants show sex. They may stall for awhile, but they should be OK. Be sure to handle them gently to avoid shock. You might consider using a small amount of SuperThrive right after the transplant to avoid shocking the plants.

Hope this helps ...

Vi