My pictures didn't really convey what was happening so I didn't end up starting a post in the infirmary. I tend to freak out when I see something happening. The good thing about that is that I catch stuff early before things get out of hand! Your assumption of root related issue(s) seems to be correct and not a nitrogen issue.
I did talk to another very experienced friend and we came to the conclusion that it was probably over fertigation causing some overall sag and yellowing issue on the lower leaves. Too soggy of a substrate leading to longer dry back times. Like 6 days for the 5 gallon pots. Strange as in that I hadn't had that issue in previous runs. I'm in a version of Basement mix with a little soil mixed into coco/perlite as to not have to water as much.
I let the pots dry back a bit more than normal and then fed raising Part B by .75 in 4 gallons of your recipe. She perked back up and has regained more green as well. The other ladies are still looking great and charging!
Many thanks amigo!!! A little Sammy for ya
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