What does Arrived at USPS Regional Facility mean?
The parcel reached a processing plant. USPS defines this scan alongside In Transit and Departed USPS Facility with a single line: the package is currently being processed or transported to your delivering Post Office.
What does Departed USPS Regional Facility mean?
The parcel left that plant on its way to the next handling point. It carries the same published definition as the arrival scan, which is a fair signal that USPS does not treat the pair as carrying different information.
Why does the same facility appear more than once?
Because sorting is iterative. USPS states that these types of tracking scans may appear multiple times from the same facility or on different days as an item is travelling, so two arrivals at one plant is documented behaviour rather than a routing error.
How many stops are left after a regional facility scan?
USPS does not publish a hop count, and any number you see quoted elsewhere is invented. The status that genuinely signals the end is Arrived at Post Office, which USPS defines as the package having reached your Post Office and being prepared for delivery, expected today or the next postal business day.