Is this a deficiency of some sort

Dude you're not looked out at all, you showed no signs for all this time and likely didn't change much from the routine so I highly doubt it's lockout, you're coming up and the finish line they're going to start drawing the last bit of nutrients they can from the ends of your leaves all 100% natural, don't add anything or change your routine, stop feeding period and start flushing with ph water, wait chop, dry and enjoy....They're 100% ok

As you're nearing the end. And entering the ripening phase. Maybe just dump 5-10L of water and she should unlock herself depending on your feeds from the past and ever enter ripening stage. But, drop your grow that's for 1 thing. As its defo not needed at this stage.

Okay. I've seen what you're using. Way to many cooks in the kitchen pal. She has very green leafs. Meaning she has N tox and more than likely got locked out. Also cut back on the feeding. Water/ferts. Your roots are finding it hard to breath. Hence the tips. So she's just drinking water basically. I've gotten this from having to feed from the bottom with just water when trying to rid myself of gnats. Too much water. And, as she's locked out that's all she's drinking. Cut back on what you're using. Or split them up. But defo drop the ml/l. All you need is 5-700ppm, max 2 feeds a week with soil following up with water or a very low cal or mag feed in between. Try keep your PH water/ferts the same or as near as you can. But I'd hard flush that. As she's an auto. U don't have the luxury of long flowering times to soft flush. 3x the value of your pot so if 5l 15L of water for a hard flush. Or you can 2x it and wait to see does she unlock herself and start eating again and then after a week start on nutrients again. If you do hard flush. Wait at least 3 days. And then apply a very low dose as I said 5-700ppm a week, 2 feeds with water in between to help break down any leftover residues..ie ph makers, nutrients that weren't used up. Good Growing