We Deliver For You. Sometimes. >Inspectors will try to determine which post office — and specifically what route— the mail came from, as well as who rented the truck. If they have to "try" to figure that out, then the post office is in worse shape than we realize. You can type in an address on their website and get all that information. That's assuming they all have the same ZIPcode, otherwise the tracking on some of the packages should give a clear indication of where they stopped.