In  file photo, two ABX Air cargo planes sit at Wilmington Air Park, in Wilmington, Ohio. Pilots for ABX Air, a cargo airline that carries packages for Amazon and DHL, went on strike Tuesday, Nov. 22, 2016, but were ordered back to work following a decision by Judge Timothy S. Black of the U.S. District Court for the Southern District of Ohio. (AP Photo/Al Behrman, File)

A federal judge has ordered striking cargo pilots to return to their jobs, averting possible holiday shipping slowdowns for customers of Amazon.com and DHL.

At an emergency hearing Wednesday, U.S. District Judge Timothy S. Black said the pilots would have to return to their jobs and resolve their differences through arbitration and other provisions of their labor agreement. The roughly 250 pilots, who are members of the Airlines Professionals Association, Teamsters Local 1224 and worked for ABX Air, walked off their jobs Tuesday.

“I am pleased that the court continues to recognize the value to all parties from continuing to work out remaining differences in negotiations and through arbitration,” ABX Air President John Starkovich said. “We intend to resume those discussions at the appropriate time and place in order to find solutions that are in the best interests of our customers, shareholders and employees.”

The strike, which came at the beginning of the busy holiday shopping season, affected at least 75 flights. According to the union, ABX Air helps deliver packages for Amazon.com and DHL. (Amazon chief executive Jeff Bezos is the owner of The Washington Post).

Even as they returned to their jobs, pilots called on the company to address their concerns about staffing and safety.

In a statement posted on their website, union officials said that pilots are committed to doing their jobs, but that working conditions raise questions about safety.

“We do not agree with the judge’s decision to keep us from striking, as we believe the company’s actions represent a clear violation of the status quo as outlined by Railway Labor Act,” said Rick Ziebarth, ABX pilot and executive council chairman of Teamsters Local 1224. “Rather than spend more time in court, what we’d really like is for ABX to stop the ’emergency’ assignments and take real steps to hire and retain the number of skilled pilots we need to keep up with our customers.”

Added Teamsters Local 1224 President Dan Wells: “Pilots should not have to go on strike to get back provisions of a contract that was taken away from them just to ensure they have adequate rest and time with their families, but ABX executives’ inability to manage its business has forced pilots and their families to compromise for too long.”