Handover is the peak, not the gap
The half hour around a shift change concentrates almost everything that generates work in a transport office. Two crews are on site at once, the crib room fills, the amenities are used heavily, briefing areas are occupied and the waste generated in a shift arrives all at once. Scheduling an attendance into that window puts a cleaner into the busiest part of the day and produces a poor result on both sides.
Placing the attendance immediately after handover is what makes the pattern work. The outgoing crew has left, the incoming crew has dispersed to the yard or the vehicles, and the office and crib areas are briefly at their emptiest while carrying the full accumulation of the previous shift. That is the moment where an hour of work achieves the most, and it repeats predictably around the clock.
