It's looks like a nutes burnt to me. I don't know if your nutrients list is up to date but if so you should reduce the nutrient amount after the flush. I mean you flush to get nutrients excess away so no need to be in a rush to feed after a flush , just half strength would be enough , to give the plants the time to use the nutrient that she's already have in her system and the nuts that remains in the soil ( expect if you're flushing hardly you'll still have some nutes in the soil ). Your ph fluctuation did not helped with the nutrients issue but if you can control it then no need to worry. What I recommend you is to flush... Haha once again and then to feed with half strength OR you can give her just water during the 2 next watering and then start with half strength to slowly increase to the full amount ( if the plant can handle it )