After Amazon leased 40 Boeing 767 wide-body freighters in two separate deals in March and May, Pacific Crest analysts identified seven main airports the retail goliath is now using for its home-grown air shipping service — and then pinpointed some of the routes being flown, according to Business Insider.

The airports include Covington; Allentown, Pa.; Dallas-Fort Worth; Phoenix; Ontario in Southern California and Stockton in Northern California; Tampa; and Wilmington, Ohio, 56 miles northeast of Cincinnati.

Many of those are within a 60-minute drive of Amazon distribution centers. But in Kentucky, there’s only: Hebron. Another four in the state are all closer to UPS’s mammoth Worldport hub at Louisville International Airport: Campbellsville, Lexington, Jeffersonville and Shepherdsville; those last two employ 6,000 workers. In total, those five centers make the commonwealth one of Amazon’s biggest overall distribution areas in the U.S.

The online retailer’s growing fleet saves the company an estimated $450 million a year, according to Pacific Crest. But it’s another sign one of UPS’ biggest customers could be a rival, even as the shipper expands Worldport, where it employs 22,000 workers — making it the city’s single-biggest private employer.

Outside the U.S., Amazon started competing head-on with UPS, plus FedEx and DHL this winter, after it bought the 75% of the French package-delivery company Colis Privé that it didn’t already own, according to the Seattle Times.

Even so, CEO Jeff Bezos told a high-profile technology conference three weeks ago that the retail giant isn’t aiming to compete head-on with UPS and other shippers it now partners with. Instead, Amazon wants to pick up the slack when delivery services can’t handle the final stretch.