Final stretch must do?

Yoo ! Doesnt look like burnt to me, I’d say it’s lacking in phosphorus or maybe calcium. Nutrients burn make the tip of your leaf going yellow and bending up and can go all around the leaves. Good luck

I have not heard the phrase "84 and door" before but it sounds neat, I don't think its a golden rule though. Your plants are looking a bit overfeed at the moment and that discoloration could be from a bit of a salt buildup in the soil locking out some nutrients or a lack of some other nutrient not related to a buildup. Its mimicking Potassium deficiency, Also to much Nitrogen as Nh4 with low amount of NO3 will lock out potassium. magnesium and calcium. This is what its looking like to me, but play aorund with your nutrients and maybe lessen up on the N and try and get some runoff with your next water to leach some of it out. Be careful not to water to fast with soil as it can compact it and cause other issues. Good Luck!

No that's not nutrient burn. It's on the lower leaves and it's more a natural looking fade or senescence. Your plants look good.

No point of thinking its nutri burn while its only 1 older leaf which is slowly yellowing and drying. It might have just a little bit too much N, it seems to be cause of darky color of leaves. Those tips that you mentioned, and if its 60 day of life, can be result of a low amount Mg. I dont saw u using CalMag so thats my guess it will help her. Ur plant is in really good health, its first signals of her needs. Try CalMag and lower doses of others nutri's for 3-4 days.

Yes this is a nutrient burn. The next feedings cut the nutrients in half and water till 0.5 liter runoff. Let the top layer of the soil dry completely before watering again. Then you can continue with 75% from the nutrients that you are giving now. That should be enough till harvest. Enjoy the last weeks you are doing great!