I've switched to continuous light now for clones and veg. No point even messing around with various photoperiods. Continuous means more growth and less temperature and humidity variation. I read that 24 hour is good for cuttings so might as well just use it for both. However, when I switch to flower I'll use 24 hours of dark on the first cycle to compensate. Whether or not that will make a difference I don't know, but it's easy to do so why not? BTW, I read one article that said that a certain amount of light energy supplied over 24 hours produces more growth than the same amount supplied over a shorter photoperiod. Meaning dim light continuously beats bright light periodically, adding up to the same DLI. I'll see if I can find the article. At least it works that way with some plants, can't say how weed would react.