:smoking: oh how I wish I could trust those pH readings

.... you didn't amend your blend with additional lime did you? Otherwise, both are peat based, and naturally mildly acidic,...AN nute's are stable in pH as well, and you're using RO water--zero buffering capacity in there! ... sooooo, as usual, the question is if this is a lack-of defc., or a pH lockout... I wonder now, because if the pH was that high, there'd be Fe defc. symptoms by now; Fe locks out fast by 7.0,... new pics do help plenty! .... Here's my thinking: the bottoms look like plain 'ol' N defc., hardly unusual at this stage (and given AN's mildness and pH lockout of N is nearly impossible)... the mids-to-uppers, a tougher call,...both Fe and N defc. can start off looking like that early on,... check it out--- see the big fan, center left? note the paler centers area, greener margins (this is N defc.)-->
....Now here's a pic of more atypical Fe defc. -->
--- similar, BUT then you consider where on the plant it's hitting, and the suspect nutrients mobility within the plant; Fe is poorly mobile, so will pretty much always start at the tops, or tops will look the worst.... N is the opposite, fully mobile within the plant, and as such it's the lowers to lowest that get tapped into first and worst; that said, this all just might be N defc.... Plants take up and store N whether they need it or not, it's automatic! but if she's been running on thin soup because of the mild AN nute's, she may not have much in reserve, forcing this early tapping,... and mobilizing nute's takes energy away from other stuff--like blooming, which might be why she's stalled out some-?..... So, w/o an actual pH reading, my best guess is the pH is likely okay after all, (no signs of acidity lockout; P usually shows first); try a little extra N (grow nutes part of Sensi) for a couple rounds, and I'd hit her with a PK booster as well, at whatever dilution you think she'll handle (it's the ratio of NPK that's important, not so much the conc.), and see if you can kick her off the lazy chair! Otherwise, she looks great Pete! Ask NW if she's a notoriously slow bloomer too,...