Philadelphia's Center City will get a boost in daytime population starting Sept. 12.

Beginning that day, Comcast will direct all of its U.S. employees, cable and corporate, to work in person on Tuesdays, Wednesdays and Thursdays, the Philadelphia Inquirer reports. A Comcast spokesperson declined to call its directive a mandate, casting it as a request of its employees. To date, the media giant has asked its workers to come to the office three days a week, but it hadn't specified which days.

Though it has corporate offices in multiple cities, Comcast's biggest employment base is in Philly, where its headquarters comprise the two tallest buildings in the city, Those buildings are staffed with 8,000 workers when full, the Inquirer reports.

“In-person interaction ... is core to our company and culture,” the memo Comcast distributed to its employees nationwide read. “We need more certainty and direction to coordinate our in-office time.”

Though Philadelphia has more of a residential population in its business core than many cities, its office buildings have hovered around half-full since early this year, leaving a hole in daytime business for Center City restaurants and retailers.

With more than a month of warning, Comcast is likely hoping it will not suffer too much attrition from employees, who either are willing to quit rather than give up full-time remote work or moved too far away from their offices to comfortably commute, something an anonymous employee told the Inquirer could become an issue. The timing, a week after Labor Day, is also meant to ease the transition back from remote work for parents.