A customs hold is a record of a decision made by someone else, plus two deadlines you can compute but cannot enforce, so the pipeline should store the observable events and derive the rest.

Engineers who build shipment pipelines are used to status enums they own. A carrier confirms pickup, a warehouse confirms pack-out, a last-mile provider confirms delivery. A customs hold breaks that pattern. The decision to detain or release is made by U.S. Customs and Border Protection, not by any service you can query, and no endpoint returns the current hold state. What the pipeline can do is record what it observed, store the timestamps that start each clock, and compute the deadlines the regulation already defines. The rest is presentation, and the presentation has to be honest about what is unknown.

A hold is not a status flag

The trigger for the short clock is not the arrival of a container.…