(Bloomberg) -- About 11,000 Boeing Co. employees have asked to be exempted from Covid-19 vaccines the planemaker has mandated, according to a person briefed on the matter, a sign of backlash among some rank-and-file workers to the Biden administration’s rules for government contractors.

Nearly 9% of the company’s U.S. workforce are balking at the policy, stirring up strife at a time when Boeing is working to turnaround its finances, resolve quality lapses and starting to lay the groundwork for contract talks with its largest union. Reuters reported the extent of the pushback to the policy earlier.

The aviation titan has shifted its deadline for workers to comply to Jan. 4 from Dec. 8, in line with the new White House rules, IAM District 751, Boeing’s touch-labor union, said in a post on its website. 

“Boeing is committed to maintaining a safe working environment for our employees, and advancing the health and safety of our global workforce is fundamental to our values,” the planemaker said.

The tough stance on Covid shots adopted by United Airlines Holdings Inc. survived an initial legal challenge Monday. A federal district judge in Texas rejected a bid by some United workers to prevent the carrier from placing them on unpaid leave for refusing Covid vaccines.

Read more: Judge Rejects United Air Workers’ Bid to Block Vaccine Rule

IAM, which represents about 24,000 Seattle-area machinists, has been pushing Boeing to adopt a more flexible standard set by the Occupational Safety and Health Administration, a U.S. agency. It allows for employees to submit to regular testing in place as an alternative to getting jabbed.

The union also said in a Nov. 5 web post that it would support members with a religious conviction against the vaccines. 

Such beliefs are “not required to be lifelong, in-line with an organization you belong to, it can be uncommon and newly held,” the article said. “If you submit your opinion that this mandate is unconstitutional, not legal or a violation of your civil rights then your request will most likely be denied as it would not be a sincerely held religious belief.”

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