Apple’s corporate employees will soon be making a gradual return to the office, two years after the COVID-19 pandemic took hold. In a memo to staff, CEO Tim Cook said workers must be in the office at least one day per week as of April 11th.

Starting on May 2nd, workers will need to be in the office two days a week at minimum. As of May 23rd, they’ll have to work from the office at least on Mondays, Tuesdays and Thursdays amid a shift to a hybrid work model.

“In the coming weeks and months, we have an opportunity to combine the best of what we have learned about working remotely with the irreplaceable benefits of in-person collaboration,” Cook wrote in the memo, which was seen by Bloomberg and The Verge. “It is as important as ever that we support each other through this transition, through the challenges we face as a team and around the world.”

Apple had been attempting to bring employees back to offices since June. However, it delayed those plans multiple times as COVID-19 cases surged. As part of a hybrid work pilot, staff will receive an extra month of work-from-home time this year.

Earlier this week, it emerged Apple made it optional for vaccinated corporate employees to wear masks in regions where they’re no longer required by local regulators. Masks are also once again optional in Apple Stores in some locations. The company has mandated twice-weekly COVID-19 testing for all employees.