No more so than the sun rising.this is my first grow its been on 24/0 for this first week and im switching to 18/6 later on.
you can stunt the growth of your plant when you shine light at your plant so if the light comes on after the 6 hours of darkness wouldn't that affect the plant?
i veg for 24/7. switching over to 18/6 will be alright you wont harm the plant. good luck manNo more so than the sun rising.