chasv77answered grow question 5 years ago If you are asking, "did my light coming on 5 hrs early, cause light burn", I would have to say no.
Timers are constantly screwing up, or power outages wreak havoc with your setup timings, but I have not seen that symptom.
I see in your diary comments, you thought you saw toxicity earlier, and had exposed it to sunlight?
This may be a previous issue, and moving plants from grow lights to natural sun, to me, would make the plant react differently.
IMO, if your grow lights do not provide IR and other natural (non-blue,non-red) lighting, that could be a problem.