how did they know

[Katia]

Several years ago, I used to mail Christmas cards. (I've dropped out of the practice over the years for various reasons.) Back then, I found it odd that of the cards that I mailed the same day, the ones that went outside my hometown only took 2-3 days to arrive at their destinations, while the ones that had addresses within my own ZIP code took over a week!

Similarly, I have received cards from people outside my current city of residence 2-3 days before cards postmarked the same day sent by people living less than 5 miles from me (and presumably processed at the local post office branch).

It used to be that I could count on something mailed within my state, at least much of it, to get there the next day... obviously not the case anymore... (I would expect something I mailed to someone local to still go to one of the hubs, though.)