I'm dealing with this kind of problem right now, and assessing the damage. I simply removed the stupid extra light I put into my grow, and I'll watch very carefully over the next week. I'm thinking of an early harvest to keep the girls pristine. I already posted that, but since you want to...
...further to my post above, in case anyone is assessing damage from light vs. distance, the affected plants were all within 3ft. of a 20 watt led. It's a far cry from an underdriven half-watt indicator led.
Yes. I added a smaller led spot-light just to fill in what I perceived to be an area of low light, and set it for the same 12/12 as everything else. At some point, that timer failed, and that single led light remained on 24/7 for what I suspect was a week. (It was a small led, about 20W.) My...