Okay, in an update to the initial press conference, Postal (mis)Management has stated that medicine pouches will be delivered, as will packages. Only letter mail will be held until Monday for delivery, which begs the question how much they actually think they're going to save?

Carriers will still have to go out to deliver the parcels, small bundles, and the packages that UPS and FEDEX drop at the door to the post office for delivery.

That's not going to be much of a savings. (unless, of course, you're an accounting firm hired by the post office to PROVE that it's going to save money!)