The tech giant IBM, once a pioneer in the work-from-home concept, is now calling its employees back to the office, the Wall Street Journal reports. The change is rattling workers. But, the company says the move is vital for their growth.

IBM Has Embraced Remote Work For Decades

Many of the people who work for IBM have taken advantage of remote work options over the years. As early as the 1980s, IBM began installing “remote terminals” in some employees’ homes. By 2009, 40 percent of their 386,000 global employees worked from home.

Like other companies who’ve embraced the model, they noticed some important benefits. Allowing employees to work remotely reduced their office space needs by 78 million square feet, which saved them about $100 million just in the U.S.

Because the practice is so longstanding and widespread, the news that a change was coming landed hard for a lot of employees who’d grown accustomed to the remote work lifestyle.

“Everyone I know is very upset,” one employee told Quartz, which also reported that IBM employees say many are looking for new jobs. According to their sources, there is even some suspicion that the move might be an effort to covertly downsize the company. In either case, it’s a dramatic shift in policy.

Why Co-Locations Are Replacing Remote Work Options at IBM

Around 2,600 members of IBM’s marketing department, along with a number of IT employees, were told in February that they would no longer be permitted to do their jobs remotely. Instead, they would be required to work in one of six “co-locations” in Atlanta, Austin, Boston, New York, Raleigh, and San Francisco. Many will need to relocate in order to keep their jobs.

A spokesperson from the company told Business Insider that marketing teams were being directed to these locations to change and improve the process of their work.

“Marketing is no longer a ‘waterfall’ work process, where work is handed from one person to another,” the spokesperson said. “It is an iterative process, where the effects of changes in a campaign can be understood live, and responded to in real-time.”

By Gina Belli, PayScale