A Biden administration appointee has agreed to lock in hybrid work protections for tens of thousands of Social Security staff, part of a slew of organized labor efforts that complicate President-elect Donald Trump’s efforts to reshape the federal workforce.

The American Federation of Government Employees, a union representing 42,000 Social Security Administration workers, reached an agreement with the agency last week that will protect telework until 2029 in an updated contract, according to a message to its members viewed by Bloomberg.

The new deal, signed by President Joe Biden’s just-departed SSA Commissioner Martin O’Malley, will let workers “maintain current levels of telework,” AFGE chapter president Rich Couture wrote.

Under those current arrangements, in-office requirements range from two to five days per week, varying by job, according to people familiar who spoke on condition of anonymity because the new agreement has not been publicized.

“This deal will secure not just telework for SSA employees, but will secure staffing levels through prevention of higher attrition, which in turn will secure the ability of the Agency to serve the public,” Couture wrote.

An AFGE spokesperson declined to elaborate on the message. A SSA spokesperson confirmed the independent agency “memorialized its preexisting telework policy in its contract with AFGE,” and noted that managers can still make temporary changes based on operational needs or performance issues.

Unions have been pushing the outgoing Biden administration to extend existing collective bargaining agreements with federal workers in advance of Trump’s inauguration next month, according to people familiar with the discussions who spoke on condition of anonymity to discuss private conversations. Some union leaders are urging the current White House team to issue an executive order calling for such moves.

A federal Office of Management and Budget spokesperson declined to comment.

Trump has asked billionaire Elon Musk and entrepreneur Vivek Ramaswamy to lead a new task force aimed at cutting government spending and streamlining operations called the “Department of Government Efficiency.” Musk and Ramaswamy have said they plan to cull the federal workforce and eliminate work-from-home policies.

“Requiring federal employees to come to the office five days a week would result in a wave of voluntary terminations that we welcome,” they wrote in a Wall Street Journal op-ed last month.

The Trump transition team declined to comment directly on the union contracts.

“Under President Trump’s leadership, the Government Efficiency effort led by Vivek and Elon will target waste and fraud throughout our massive federal bureaucracy,” spokesperson Brian Hughes said. “They will work together slashing excess regulations, cutting wasteful expenditures, and restructuring Federal Agencies.”

Organized labor represents over a million federal government employees, and AFGE is the largest federal worker union. Legally-binding union contracts, which dictate terms on working conditions, can be amended during, or extended beyond, their existing timeframes.

While they don’t supersede federal law, contract terms can restrict agencies’ discretion over how to manage their staff.

AFGE members at the Environmental Protection Agency in May ratified a contract with management that includes new “scientific integrity” safeguards meant to protect their ability to discuss their work with the media and report alleged scientific misconduct without suffering from retaliation. Attorneys at the Department of Justice have been organizing with another group, the National Treasury Employees Union, trying to secure union recognition before Biden leaves office.

Collective bargaining agreements may not deter Trump, Musk or Ramaswamy, who have signaled they plan to challenge precedents limiting executive authority. But reneging on a contract could lead to protracted legal disputes, as well as protests and pushback from lawmakers.

A US president “can’t just set aside lawfully signed collective bargaining agreements, without the unions’ agreement,” Indiana University law professor Kenneth G. Dau-Schmidt said via email. “The US government has to live up to its agreements, too.”