Unless the actual TIME reflects this, if you have those on your schedule, it could mean that you have borrowed hours from those departments.
He said during the day, so I'm assuming the he meant literally during daytime, and not the normal night-hour shift.
But, yeah, what this guy said. I was actually originally hired as "night stocker" according to my application that they filed (I took a glance at it before they put it away), but never worked later than 11PM. And there's been times when I've been officially scheduled in one department for the week, but worked in another. They often do this to use up hours that are left-over, but do not want to pay the current department any overtime.