Through the grapevine shipping with USPS is going to be severely delayed out of California and New York. Could apply to other states as well in the near future.
Reasons: Carriers retiring, quitting and calling out sick. The new postmaster general has a top down policy now of no overtime for any carrier going forward. If packages can't fit into an 8 hour route or distribution shift leave them for next day or later. There are severe backups in parts of California and New York.
Only services still not affected at the moment are priority express one day and certified mail pieces. I have two packages that have been stuck in Los Angeles now for 2-3 weeks with no tracking updates.
Vent your frustrations here. I am going with the "it is what it is" mentality at this point. If you resell or sell anything and use USPS to ship keep this in mind.