Paid for UPS shipping and the package was immediately sent to the US Post Office.

It could be UPS service with a USPS handoff. International shipping probably works best when USPS is used to go through customs. They might hand it back to UPS for delivery or not. I use USPS all the time for international, no issues.   

Thanks for that. I've shipped internationally with UPS several times and shipping always stayed within the UPS network. I thought it might be something new in this Supply Chain Crisis era.

It's significant money for a 20-pound box with that UPS fuel surcharge that the post office doesn't charge. EMS (the post office) and Global Express is a lot cheaper.

Does FedEx do this too? The FedEx quote I got was about the same as UPS before I chose UPS.

OP here. The strange thing is that I originally got a UPS tracking #, and a day later UPS handed it over and the US Post Office gave it a new Post Office tracking #.

So it looks like the UPS Store just handed it over to UPS as normal, and the UPS decided to transfer it to the Post Office (immediately, locally near me).

The UPS Store probably doesn't even know about this. But if it happens normally these days, I guess I learned my lesson. No need to pay more for UPS anymore.

Someone is shipping something to me and apparently, the same situation..

When I was importing motorcycle parts from the EU I had the same issues and finally had FedEx pick up form the vendor and ship to the US. Got here faster and cleared customs fast.

I was importing form the UK, Italy, Austria, France and Estonia.