Night sort in the Klang Valley is a different building even when it is the same address. The walking lanes change, the radio is louder, and inbound from late feeders lands in bursts. A handheld scan at 1:40 a.m. can be a real event on the floor and still mean nothing to a recipient who opens a tracking page at breakfast.
We watched a July night sort where inbound scans were disciplined and the morning board still looked idle. The notice vendor was set to fire on “out for delivery,” and “out for delivery” was still a bulk action at 8 a.m. The night work had been real. The recipient’s page had no permission to speak until the roster ticked.
There is a second, quieter miss: the scan happens, the status updates inside the hub view, and the recipient view is fed from a delayed copy. Supervisors who only watch the hub view will swear the notice went out. The customer desk, reading the public trail, will swear it did not. Both screens can be right about their own clock.
If you want night work to show by morning, name the event that is allowed to notify. Some desks choose the inbound scan. Some choose a quieter “received at destination hub” that only fires once the bag is on the belt, not while it is still on the feeder. Either choice is a choice. Leaving it unnamed means the night crew works for a screen the recipient never sees.
A timing review of this kind needs send logs with actual clocks, not a daily count from the vendor. If all you have is a total of messages, we will say at quote stage that a timing table cannot be built. That sentence saves everyone a week of staring at a number that cannot answer the question.