Apple and Facebook employees will not return to their respective offices until January 2022 as the Delta variant continues to spread.

Apple has told its staff it will give their employees one month’s notice before returning to work as they continue to monitor the spread of COVID-19.

The decision comes as the Delta variant has been surging in states such as Florida, Louisiana, Oregon, Hawaii, and Mississippi. The company will increase its testing program to as many as three at-home coronavirus tests per week.

Facebook released a statement saying “Given the recent health data showing rising Covid cases based on the Delta variant, our teams in the U.S. will not be required to go back to the office until January 2022. We expect this to be the case for some countries outside the U.S. as well. We continue to monitor the situation and work with experts to ensure our return to office plans prioritize everyone’s safety.”

Facebook will also require all employees to wear masks when on company property in the U.S. regardless of vaccination status. “The health and safety of our employees and neighbors in the community remains our top priority,” a spokeswoman for the company said in a statement.

The two companies originally planned to return in October but decided to postpone their return dates amid public health concerns.

Amazon, Alphabet, Lyft, Wells Fargo, Google, Humana, Microsoft, U.S. Bancorp, American Express, and Uber have all delayed return dates to their offices.