Yellowing edges in late flowering

My girls have deficiencies since they was switched 12/12. Its day 39 in flower now and they stopped yellowing last week but now they r doing it again. I know its late and yellowing is natural but i still wanna leave them getting fatter for few weeks. I like couch lock anyway so its not a problem if crystals go amber a bit.

The purple leaves mean they r starving for Phosphorous and u can also see some N def on older leaves. (they lost a lot of fan leaves earlier ) As u can see i have many deficiencies in the same time im not sure why. Im growing organic so the soil is BioBizz All mix and its supposed to buffer the ph down. I always let the tap water sit out for 48 hours to get rid off chlorine and after adding nutes its ph is around 7-7.2 .

I give them 4ml/L Bio-Bizz Bloom and 1ml Grow every watering (they need water once a week) which is considered to be a high dose but it seems they want more. Im in doubt cause if its not organic i would be definitely sure im overdosing them but as a i know its hard to achieve in organic environment.

The new issue is new growths are yellowing on edges and im not sure what that means. Potassium def?

Strain: Nirvana Northern Lights
Light: 250W CMH
Pots: 18L
Soil: Biobizz All mix
Nutes: BB Bloom, Grow, Unsulphured molasses every 2nd watering

You're about right on track. You may have the start of a ph problem, but it doesn't matter at this point. When you see the entire or most of fan leaf turn yellow overnight, the plant is pulling that nutrient out of the fan leaf to support bud growth.

You really only have a problem if you've lost all your fan leafs and even the leaves closest to the buds start yellowing. I think you'll have some pretty nice smoke when it's all done.

The only time it's a bit concerning is when it's happening on the upper part of the plant, as is in your case. But, again, so late in the game, you should be able to hold it together long enough to finish.