Q. Once upon a time, our mail always arrived at the same time of day. But in recent years it arrives each day at wildly varying times. Did something change at the post office?
A: The Postal Service reorganizes carrier routes as mail volume and population patterns change. That can result in an address consistently falling earlier or later in the delivery schedule. When delivery times fluctuate, the most likely explanation is that a regular carrier is not working that day, causing their route to be divided among other carriers.