A: Timers are attached to part transfers out of a station, rather than the times that the parts were transferred in.

If you transfer parts into a station on Thursday at 3pm, pause the timer at 5pm, and then resume that timer on Friday from 7am to 9am, all 4 hours of work will be be counted as 1 segment.

Since the transfer out of the station happened at 9am, the start time will reflect "5am" (4 hours of billed time, beginning 4 hours prior to the time the parts were transferred out).