I think plants have an internal clock. It may be cool in your building but I think they can still see that it is getting darker earlier and before you get there in the morning I am sure the plants notice the sunrise is different. The light and earth signals the plant it is time to rest. Regardless if they are outside or inside. I think they are one with the earth.
My tropical plants that are in the basement and laundry room do not have a noticeable window but every Late Feb - March the plants start to wake up and pop up out of the soil in the pots. I do not dig up my tropicals I keep them all in pots and bring in the pots without disturbing the roots or plants.
