I have some pants about 16" tall that i put on the wrong timer and they spent about 3 weeks on 12/12. They have started flowing and i want to put back in Veg.
I’ve heard put on 24 hr light for a bit then switch to 18/6. Anyone have any experience with this? How long it takes to go back to veg? Any way to be sure
Nope
24hr light straight for weeks. You will see single leaflets and new growth.
Wouldnt hurt to uppot first and add some microbes. Reveg is a pain. Sometimes takes a month but makes for beast plants that you already know tge sex of. I reveg clones off of good growing females and mother one of the clones. Probably not the best way but i get solid mother plant that way. But you want 24hr light and to get your roots up n active. I pinch tge budlets off. Itll pop new tops.
Or you could monster crop some clones and finish the mom.
I put flowering mother back into vegetation using an 100w infrared light for only a few days 
I did it by mistake mind you 
but I discovered a pretty neat trick!