How long after gender ID before pollenation?

I have two feminized plants and two regs growing together. I want to snatch the males asap. I am vegging for 4-5 weeks and the switching to 12/12. I do not have room to put clones in 12/12. I have to do it this way. Lets say I was out of town for 3 days and the first day out they started showing the beginnings of balls, can I get remove them 3-4 days latter without pollenation? I just do not want to miss the window.

I took my males out of the grow room and separated them outside to save some pollen.. Took them another two weeks to start opening the pollen sacks.. So total about three almost 4 weeks. This is just a rough guide, every plant is different.