Priority Mail Express 1-day shipments sent between December 22 – 25 will not be eligible for postage refunds unless the package is not delivered or delivery is not attempted within two days of the mailing date.
The USPS adjusted its Priority Mail Express refund policy in anticipation of higher volumes over Christmas week and unpredictable weather conditions that could affect one-day shipments during the holidays.
Normally Priority Mail Express (PME) service comes with a money-back guarantee based on its service features.
Note that the USPS is also adjusting its Live Animal Holiday Acceptance Policy over the holidays:
“As a result of the limited transportation availability during the holidays, any shipment of live animals will NOT be accepted on December 22, December 24, December 29, and December 31 through any channel. The normal acceptance policy will resume on January 2, 2019.”