I'm working on the LST and I have a couple of questions.. at what point do I quit doing LST and let the plants grow?
You don't want them getting root bound. That is the main thing stopping how far you can train. Train till you have reached or nearly reached your desired canopy size.
Like Bohbo said... I train until i reach my desired canopy which is usually dependent on grow space and # of plants. I leave it tied the way it is and continue to just tie back leaves to show bud sites (you can either tie them back or tuck, whichever you prefer, i do both). Then somewhere between the 4th-5th week of flowering until harvest i will let my plants loose from all LSTs.
but why would you train your babies all that way only to let them finish normally? IMO, it looks fine. the more exposure the nodes/budsites get, the better/more growth
Personal preference. There will be a growth jump when you release them. So if you have extreme height restrictions you would probably never release them. They stay pretty consistent with how you trained them in the first place so it's not like they go back to being completely straight up again.
just keep doing what ya doing mate it will give ya loads bud sites n yal be able to tame her in strech that way it wont get out of hand .
Because the effects/benefits of LST are "locked in" at that point. The canopy is even, the secondary growth has been maximized, the stems and stalks are hard so will hold their LST'd shape, etc. They could still get a little taller but not much. I usually untie at the start of 12/12 to let them enjoy the early flower growth spurt as much as my space will allow, and if I need to I can always re-tie them.