HST in bloom season?

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.