¿Quemaduras del foco?

Looks like it could be pH issues, just with the fact the leaves have tip burn aswell as all the leaves turning yellow like the plat haves nutrient lock out, leaves will never go back to normal now but I would check you pH for the final few weeks so you don't loose out on any weight as the plants draining the nutrients from the leaves

Looks fine to me

I had the same phenotype on these Dark Devil Auto seeds. Check out my diary. As others said, you can slightly increase nitrogen but this looks to be pretty normal for this strain! Really amazing plants.

The leaves will turn late in flower but you can always spoon feed them some nitrogen to get them to the finish line, not too much though maybe 1/4 of a normal veg dosage, do that with your normal feeding schedule or you can foliar feed for quicker results. But it is pretty normal for them to look that way when you harvest.