I have never watered her until run off...I give her about 2.5 litres once a day
If this is all coco coir and perlite, this is the issue probably. Bet money or partly the issue. I didnt have enough runoff and I was in plant problem section forgetting to check runoff.
Should be equal or only a few points higher in ec. Ex. ec in 1.8, ec out 1.8 or 2.1.
Feed atleast twice a day or whatever prevents drying out. It can and should lose some moisture which is different than bone dry to the touch.
The plant is in limp mode probably and will finish a little late if thats ok. More light in the 600-900ppfd range in 24 hrs will help, its counter productive to give an auto dark time.
Especially if its not needed. It more often than not is beneficial to autos.
I dont know about all the talk about dark time being beneficial to autos but people compare it to I think cabbage grown in alaska under 24/0. Im a believer im that idea.