I don't exactly understand the relationship between P.S. & UPS. It would seem that UPS taking P.S. packages would be counterintuitive but I'm glad that they do.
I wonder too. My assumption was that PS purchases shipping in bulk from UPS (and USPS) and resells it to retail shippers on their website. Their role seems limited to generating shipping labels; they have no physical involvement with packages. It would be interesting to know.

