Light schedule time

Not much, 18/6 is optimum. Cannabis can only grow so much in any 24 hour period and this growth tops out at about 18 hours, meaning running your lights any longer than 18 hours is basically a waste of electricity. 18/6 has been derived at through 80+ years of research and is not a random number. Unless you were doing an experiment with clones and using EXACTLY the same growing EVERYTHING, saying that a plant finishes a week earlier than "normal" by going to 20/4, really doesn't hold much worth. Hope this helps,...... Organoman.

If its a photoperiod i would leave it @ 18/6. If its an autoflower i find if i run @ 20-4 they seem to finish up to a week early.

Not going to do much for your grow, I've actually tried it, I've seen the best results come from 18/6 it gives the plant time to rest.