The tracking is only good to the border.. after that the sender cannot track the item at all, neither can the buyer. All tracking does is tell you it went to the airport sorting depot.
You wont know its been delivered until the buyer tells you so.
This is how it works with Aus Post international anyway. recent set of stencils sent to USA with tracking... buyer is emailing me asking why the item appears to still be at the airport depot in Australia and not moving..... it is moving, but its no longer trackable from a different postal service. Item arrived next day after the email
