Pretty normal for some strains to "predict" lights out, no doubt if you look one hour before lights on, your plants leaves will already be standing up waiting for the lights to come on!
They obviously have a healthy and strong circadian rhythm, something a plant growing with a very un-natural and detrimental 24/0 will never have.
Only someone who does not understand photosynthesis and how plants function would ever recommend growing for weeks/months without giving their plants any of the sleep that they NEED to be healthy.