The USPS doesn't normally pay overtime. They decide how long it should take a carrier to do a route and theoretically design the routes so that they can be done in a normal workday. The management is notorious for withholding mail from any carrier whose route is going to be audited so that it can be done easily in the allotted time. Then, after the audit's over, release the backlog and make the poor SOB work whatever hours it takes to get it delivered while being paid only his/her basic pay. They held huge amounts of mail during the holiday season when they do pay overtime so they could hold down the OT bill. That mail is now being released on to carriers who will work overtime without overtime pay to get it all delivered. Sale flyers/coupons that expired weeks ago suddenly showing up in your mailbox are indications of this underhanded management.