Microsoft: Office 365 for Mac subscribers must run newer editions of macOS
Microsoft has warned Mac subscribers of Office 365 that they must be running either macOS Sierra or macOS High Sierra next month when the company updates the productivity applications.
"As of the Office 365 for Mac September 2018 update, macOS 10.12 or later is required to update to the new version of the Office client apps for Mac and receive new feature updates," Microsoft announced in a support document.
Microsoft will probably deliver the Office 365 September update around September 11 or 12 if it sticks to the usual monthly refresh schedule.