Choose which custom attribute on the order holds the ID of a pre-booked shipment (PreparedShipmentId) sent to Specter.
Good to know
If you leave it empty, the provider ID from the order's shipping is used.
Enter 0 if you don't want to set it at all.
If the value sits inside another attribute, use dot notation. For example, if the attribute msuodc_assignments contains {widget_agent: SE12345, prepare_id: 1234567788}, enter msuodc_assignments.prepare_id.