If/when to top and when to flower?

Hey guys, this is my first grow and I got these 2 month old babies going under an Area 51 xgs-190 and I just want to know a couple things based on the pictures you see. I have already trimmed some of the lower growth to "lollipop" the plants, but should I also top them to increase the spread and possibly the yield? If so, WHEN should I top them?
Also, based on my setup, how much longer, if any, should I let them go before switching to 12/12 ?



Thanks for looking, Please comment.

First of all your ladies look great/healthy. I would flip to 12/12 now and not top/fim, it will just stall your grow. They have good structure for your height dimensions.

If stretch gets out of hand , supercrop them...................be safe grower

I agree just flip them now, though you are going to want to lollipop after they are finishing their stretch and starting to bud so that you do not end up with a lot of lower fluff, this is just my opinion of course.

They look plenty big enough to put into flower.
If you let them veg much longer, you may run into height issues later on.
It's too late to top them, but you could still pinch/supercrop them, to help control their stretch.
Nice looking grow, sir, good luck.