Yellow parts on bud positions

Also how close are you light try moving those back about 8-12 inches that might clear it up too.

First I would check the PH and make sure your around 6.5. Than sometimes Iron defiency can cause new leaves to turn yellow. So go buy some Cal Mag and get it about 5ml per gallon. If those two tricks don't clear it up. I would say that it's a nutrient defiency and you might be overfeeding if to much of something. So if the cal mag and ph dont work. Flush your plants. Run good 6.4-6.6 ph water through you containers about 4-5 times. This should flush out some nutrients. There's a few things I think could be going on, so this is best advice I could give. If you haven't been feeding it any nutrients at all than you can ignore the part were I told you to flush. It so hard to tell exactly whats going on because i dont know nutrients or feeding schedule. But defiantly check PH and give it some Cal Mag it has iron in it. Good growing don't panic your plant's should be just fine. I have seen people not do anything to fix the plant and at the end the buds where still pretty good. Step 1 check ph, Step 2 add Cal Mag (might be iron defiency), Step 3 if other steps didn't work FLUSH it.

Hey, it seems a light burn, elevate your lights 20cm for sure 😊