Factbox: What are the U.S. Postal Service changes that have stirred controversy?

United States Postal Service (USPS) mailboxes are seen stored outside a USPS post office facility in the Bronx borough of New York City, New York, U.S., August 17, 2020. REUTERS/Mike Segar

(Reuters) - A U.S. Postal Service internal watchdog is looking into service disruptions that have slowed mail delivery ahead of a presidential election that could see up to half of U.S. voters casting ballots by mail.

The new Postmaster General, Louis DeJoy, has ordered changes in mail delivery policies since taking the reins at the agency in June, which has fueled concerns over the Postal Service's ability to handle the ballots.