I have never grown in peat but if it is like soil it will be slower on seeing changes verses dwc or coco. What it is doing is  there is not enough NPK in your medium so it is pulling it from the leaves etc. Her goal is to produce a flower which usually has seeds to reproduce. She will eat herself to reproduce if you are not feeding her what she wants. Veg is kids meals and flower is the China Buffett. lol I think you are on the right path now. If you look at your feed charts you will see a drop down in nutrients in the last couple of weeks.