I ship a lot of stuff I have out for sale on outdoor trader sites and track the shipments. Quite often I see the USPS regional centers playing “ping-pong” between themselves and end up seeing the original delivery estimate date being delayed 1 or 2 days.
I haven’t figured out why, though. I use printed labels and they are very easy to machine read. I can only guess it happens because of logistics (maybe a truck was full or they decided to pong it because they “hold” a package at a center waiting for the next truck to the correct place). It’s frustrating.
This is what I have noticed recently. Several of my packages—nothing that would raise flags at all—have ping-ponged around and actually go missing in tracking to suddenly pop-up a day later. I see this as not the normal USPS/UPS behavior, but odd instead.