Concrete Pour On Floors

I'm catching up with the time-lapse videos, and noticed that the concrete floor pour began on Sept. 25th. The winter sun has moved into position to create some glare in the Webcam lens. But you can catch glimpses of the boom arm of the concrete pump in the back alley. Looking at several days, you can also now tell that the floors are all smooth and dark gray, rather than the corrugated steel that was visible previously. Otherwise it's difficult to see what work is being performed each day. Plumbing and electrical work are obviously being done, but you can't really see that.