lst and flowering

can i still lst once i switch to 12/12 and if so how long till i stop?

Eish brother...

You can, as some varieties grow faster when flowering like most Sativa varieties. LST can be done as much as you'd like, all preference as LST is method to Train the plant to grow the way you want to short of topping your plant - high stress training.

LST is a ongoing process, it slows down close to harvesting but your "top" or Crown of the plant is continuously growing, depending on how you LST it.

Peace

cheers watched a few vids of it now think i got the jist of it

Your plant should be pretty well trained by the time you flip. After the switch you will likely just be making minor adjustments to keep the canopy the way you want it. Avoid anything drastic during flowering, it can slow down the process