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Delivery Scheduler

  • Legs, dwell, cut-offs and punctuality, shared by road, rail, sea and air.

Each leg is a departure, a duration and the zone it lands in. The summary card leads with the ETA in the last leg’s own zone, the door-to-door span, and flags for what happened along the way: a DST change, a Date Line crossing, or a handoff an offset table would get wrong. An offset table is a fixed UTC offset looked up for each place, with no DST. A missed connection turns the same card into a failure state naming the leg.

A toggle switches between two charts of the same journey. Route draws one segment per leg, never sized by how long the leg took. To scale draws the same legs on a real time axis. Where an offset table would misread a handoff, both charts flag it. That offset-table reading is the only value the widget computes itself, and it is always labelled naive. Everything else is the real scheduleDelivery call for what is on screen.

1. Build the journey

A truck leaves Chicago at 08:00 on 8 March 2024 and reaches Los Angeles at 05:00 on the 10th, three hours after the clocks sprang forward. Two hours of handling, eleven days at sea, a day at the Tokyo terminal, then two and a half hours by rail.

For a published local first departure with no offset or zone of its own.

Durations are ISO 8601: PT46H is 46 hours, PT2H30M is two and a half hours, P11D is 11 days.

① Truck · PT46H → Los Angeles
② Ship · P11D → Tokyo
③ Rail · PT2H30M → Tokyo

2. The journey, handoff by handoff

 

    • departure / arrival
    • handoff
    • missed connection
    • DST / Date Line note

      3. What scheduleDelivery returns

       

      4. What transitTime and etaAtZone return

      Every arrival is transitTime of a departure and a duration, and every local time is etaAtZone of an instant and a zone. These are the two calls for one leg. Their results are that leg's arrival and localArrival in step 3.

       
       

      Worth trying: the ship at 06:30, a missed connection — scheduleDelivery returns null, and a note says why. Then leg 2’s departure typed with no zone — the timetable’s printed 07:30 is read on Los Angeles’ clock, where the truck lands, and the ship makes the connection.

      Reference: scheduleDelivery, transitTime and etaAtZone are the calls behind every value here. For a single handoff with a handling-time slider, see the Connection Checker. For the fuller picture, see the guide’s Transport: Multi-leg Scheduling.