The US Mint just emailed me my 2021-W Proof Type 1 Silver eagle has shipped. I paid extra for over night delivery. I wonder if it will arrive tomorrow
That usually means after the day it's shipped. So let's say they ship out tomorrow Thursday. Then you get it Friday. If they ship out Friday you will get it Saturday.
Key word is "usually", currently from what seems to be reported "usually" does not apply. The real question is, the post office used to refund the postage if they didn't deliver in the guaranteed time, Are they still doing that, or are they just keeping the higher postage?
Not 100% sure on this, but I believe they're honoring the Express One Day Service commitment. If not delivered the next day with Express they'll refund the shipping. Priority is definitely NOT refunded, no matter how long it takes.