I see no reason to lollipop, the leaves are pretty sparse as is. When to flip to flower is up to you and your set up. When they're about half the size that can fit in that space go ahead and flip.
Bend that tall one over to get an even canopy. I'd cut a few things off the bottom to. Then start flower anytime after that.
Maybe the bottom two nodes. I’d defol more of that then lollipop’n. If it was me I’d go thru and remove all the bigger fan leaves
I would not suggest flipping to flowering until u get ur issues taken care of. Just going off the top leaves u have a mag issue
I wasn’t feeding a lot of nutrients that’s why it has a nitrogen deficiency I watered a couple days ago should be time to feed that should fix the nitrogen problem for the cal def would I need to get cal mag
I trip out when I post and come back later and there isn't anything there. It was nothing important. Like others have said, get the plants healthy again and flip 'em when they're on a roll, you know a growth spurt. What are you using for nutrients? Carry on