Office 2016 and 2019 holdouts blame update for license deactivation bug

Users report that a recent optional update for out-of-date Microsoft 365 applications might be connected to suddenly deactivated Microsoft Office 2016 and 2019 installations. The activation bug cropped up this week and appears to mostly impact Home and Business perpetual license installations, stripping away their authenticated status and forcing users into a loop where they are asked over and over again to re-enter their product key or face deactivation or reduced-functionality mode.