When to lollipop?

So I just started flowering and I see my bottom branches below the canopy are shit because of lack of light now the plants are under my 600 watt hps so question how many weeks must I wait to cut the crappy branches off and ensure it won't start to repopulate with pop on nugs

No need to wait really. I personally cut mine in veg when I top/take clones, no sense in the plant wasting energy and time on branches that will not produce. Just my thoughts

As they grow I start trimming the bottom up. Once when I flip and again in 2-3 weeks. when they are done streching.
Come to thing of it time to clean up tonight

I would suggest doing it gradually over a few cuttings. Less stress for the plant.

Ok I'll slowly take them off for the next week these are definitely branches that I'll cut off