This week the plants grew quickly, practically doubled in size, the first flowers are appearing. I think I will have problems with their height hehe. They are completely healthy, they have branched well. Very robust.
If you have no other chance like changing the position of the lamp,you can do it.There won't be any huge stress compared to the risk of it being burnt by the light. What I understand from my own grows is that hst is not even as stresful as topping. it is just putting a little bit more pressure than lst. I just did it to one of my plants at the exact stage as yours,an hour ago,it's going to turn its head up to the light in a night.you can do it. this will also strengthen the stem.
N deficiency yellows from tip to base, this is yellowing from base to tip starting at the top of the plant it looks like. I'd say a Sulfur def, its a immobile nutrient to it can only go up the stem, so deficiencies would appear in the top first, as the plant absorbs it from base to tip.
@Green_Dream, Exactly friend, it smells great, eager for the harvest, I still have the bills for 4 weeks, I hope you get fat, anxious to taste it. 75 days of bloom.