A key decision and deadline is approaching for federal workers: Do they accept a buyout offer from the Trump administration and get paid through September, or do they stay at work and face what's expected to be a changing workplace culture under President Trump?

Scripps News has confirmed that at least 20,000 federal workers have already taken the buyout offer. The White House expects a rush of resignations in the coming hours prior to the Feb. 6 deadline.

The White House has estimated between 5% and 10% of the federal workforce would accept the offer, saving the federal government as much as $100 billion.

Unions representing U.S. government employees filed a lawsuit on Tuesday to block the buyout, which they claim violates federal law.

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Part of the challenge workers face is whether they would make as much money in the private sector, and whether they would otherwise be willing to accept sharp changes in work environment. The Trump administration wants more workers back in the office, with fewer opportunities to work from home.

Elon Musk is also working to downsize or shutter entire agencies through the Department of Government Efficiency.

The General Services Administration, which manages federal buildings, has also indicated the Trump administration intends to reduce the number of federal buildings by as much as 50% in the coming years.