More than 50,000 Amazon employees will return to work in Seattle for the first required in-person Monday shift in years, marking a major adjustment for the region’s commuters.

Tens of thousands of Amazon employees will return to work in Seattle for their first required in-person Monday shift in years. Now the traffic in Seattle is expected to seriously ramp up, especially in the South Lake Union neighborhood.

Amazon has demanded that all of its employees return to the office full-time, five days a week. Now, as those workers head back to the office, officials in the company’s home base of Seattle are warning that the policy may clog up local traffic routes.