The answers above are all correct. If it is taken to the post office by UPS, it is a surepost package, this is a shipping option UPS has for our customers.
Ups will carry to the post office and the post office will deliver it if you box to box service. If you have a po box then to need to give special instructions for door step delivery.
Check the tracking number. Some shippers save a few cents and use the postal service for the last mile.
Is it a surepost package? If it is those go to the post office.
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