second grow, Northern lights auto grow

you may have felt the issue by yourself, the plant got to close to your Light, and was brned by the light.. The leaves will look much worse and get brown, rise tthe light/ bind the plant down// dimm the light// get more distance to the light .......... and the plant will shine again

Then you probably have light burn. Unfortunately, unless you can find a way to fix this, it'll likely result in loose, airy buds and a decline in quality. If it's 2 weeks or less into flower, you can safely supercrop the tallest colas to bring down the height. That is my recommendation. Download a lux meter app on your phone (LUX is a good one). Your plant can take between 45000 and 60000 lux in this stage. The meter is fairly accurate on newer phones. You could also have a calcium deficiency. This normally occurs when you don't use calmag, have switched over to RO water, or if you're using too many bloom nutrients which will lockout calcium pretty deftly. Good luck!

I have some input for both of your questions. Yes this is light stress but most likely due to a Calcium and Magnesium deficiency. - For this I would add around 100ppm of calmag to your feed, keep that going for the rest of flower on your feed. The reason for this is because the fan leaves under light are photosynthesizing a lot more then the lower ones and they consume calcium and magnesium a lot more. Do not top the plant in flower, it will not recover. Don't cut the fan leaves, they are still putting in the work even though they have some scars, if this worsens it could be beneficial to chop the leaf because at that point its not doing much and just taking energy.