End of Cycle or something to be afraid

I think that @Shinsimilla nailed it. I was already looking for burn kind of issues, but this one didn't came into my mind. And observing a little the affected plants, they are on the path to feed the ones on the back. I also found some burnt later that seems like a drop. Thanks you all for your advices.

If this is present just on upper leafs could be light burn ,if its threwout kinda like wind burn .humidity should be 40% or lower if its higher it could be start of bud rot

I think the 2 plants show the same thing (first 2 Wedding Gelato, second Dos Si Dos 33). I can see the same in another plant now, common thing is that all of them are very close to harvest. Other plants that need more time do not show anything similar. I put on my diary a picture of the leaf on microscope (apparently I cannot add it here directly)

First two pics.. that absolutely looks like the beginning of botrytis/ bud rot at the stem. You pull that bud open it should be evident if you’re familiar With it. I’d give it about 50/50 shot it’s just some weird burning otherwise but I would Personally bust that open and inspect

Ye it looks like it’s just your plant fading… nothing to worry about unless it’s happening everywhere. It’s happen to me but also I was a day late of watering so I think mine was a bit of fade and dried out..

I THOUGHT I saw something in your first two pics... but nothing in the others... if the brown leaves in the first two pics aren't pulling out easily, that's a good sign that nothing is wrong however I would want to kind of bend that bud a little to see if you can see inside it a bit more... bud rot is insidious and nasty... I had a couple of grows this year that succumbed to that and had harvested what I THOUGHT were good buds - saw absolutely NO sign of bud rot on the outside - but as I was wet trimming them, there it was - just hadn't gotten to the outside of the bud yet.... So be VERY careful, and very carefully inspect each questionable bud and look for it as you're trimming. You're luck, if there IS bud rot, that your grow has gotten to the point of being harvestable (i.e., amber trichs!) ... so good luck. And btw, if you DO find it, you don't necessarily have to pitch the entire bud - you may only have to cut out a portion of the bud - but immediately spray that area with a 1% H202 solution to kill any spores. Hope against hope you don't have anything to worry about! Good luck!

Looks like typical fade due to nearing the end of its life cycle, in my opinion. Happy harvesting!