Root cause:

An update was introduced to the backend data sync process for shipments on 09/23 around 15:00 ET. This was related to shipments with both primary and secondary tracking numbers (UPS Mail Innovations, UPS SurePost, etc)

This caused shipment headers to be synced to the integration database without issue, thus passing integration test cases.
However, shipment details (packages) were not properly synced.

Resolution:

The bug was corrected and the update redeployed. Backup syn...

TEST PBD API recovered.