Give them foliar feeding of your grow solution. Make a spray bottle full of about 1/3 of the concentration you used to feed the roots. (1/3 of 1/4 strength makes it about 1/12 of the label feed rate) The leaves will absorb nutrients to help get them healthy again. ***foliar feeding should be...
I think your on target. I have split my room back when I was hand watering and tasted a BIG difference in the flower. The plants that used up their stored nutes ant the end of the cycle cured faster and had cleaner flavor.
This is solid advice and good reasoning. I have always found that a slight decrease in N at the end of flower gives me the best result for flavor and quality. I try for about 30% yellowing by harvest time with the upper part of the plant being green. I start lowering N in the last 5 days prior...