This is very common with P and K toxicity. Excess P and K causes the lockout of micronutrients and calmag. Now, you have to decide how you want to treat that. Your plants just finished stretching, so now is the time that they will be increasing their intake of P and K by a lot. So you can try to fix the problem by giving her a feed of pH'd water only. You could also not change a thing because it's possible that your excess P and K are going to be necessary now that she has finished stretching so the problem may fix itself.