My wife and I brought a package to USPS to deliver to our daughter in another state. We used a 2-day Priority box and were charged accordingly. The postal guy at the counter said it'll get there by December 18th. My wife complained "Hey, today is the 3rd and the 18th is not two-day delivery!". The postal guy shrugged his shoulders, and said " by the 18th, it's the busy season.". So much for "Priority" mail.
Hmm. I think he is misinformed. I have stuff shipping today slowboat and it will be here next week.