The first recommendation I would suggest is using something to adjust the height at which the pots sit. I also run perpetual so I can relate to your challenges (I run a lot of different strains). My plant containers are being raised and lowered consistently and my light not so much.An earlier flowering plant for instance, can be elevated to make the canopy even with the others in the flowering area. I have and do supercrop in flower, specifically during the stretch and I have notice no visible difference or negative effects on the plant. Just be careful, they're a bit brittle during the stretch because the new growth is pretty "green". I try not to do it, but when necessary I do it. Control and manage your plant canopy simultaneously with your plants' container height and the results will be a better yield and a better product!
My light barely moves, only slight changes based on what the canopy is doing overall... Think of your canopy as pieces to a puzzle that create a blanket of buds. Keep it as even as possible and you will be a happy grower

More info than you asked for and I apologize if this is all something you already know and do, but a lot of growers fail to do this and it causes excessive stretching and smaller yields.
Go Tigers 2012, go Wings, and GO LIONS!
Go take a piss! My ass is coming in HOT today at 5.2, will check again tomorrow lol
Really though, I read that urine can range from 4.5 - 8 depending on diet.