It is quick easy method but if you don't have many then moving by hand may be a better option. You don't want to much disruption in your colony. Good move.

The lag time between berth is 2 months before they will berth again. One month from berth until they will even breed again, and one month to develop the young. This time may vary between 6-8 weeks but closer to 8 weeks is more accurate. I once read on the LLL reptile sight that stated 20 females will berth 500 a month. This is very inaccurate. It will be closer to 600 every two months. I am figuring it was just a sales pitch. If you are seeing 500 a month with 20 females i would love for anyone to let me now this secret.

I have never had a roach try to protect its young that is very interesting. But then again i have never attempted to remove babies just after berth.