Software Update Menu Bar
SUMB is a native Swift companion app for scheduled macOS updates via Declarative Device Management (DDM). By utilizing a live menu bar countdown, it leverages cognitive design, giving users a constant, subtle psychological buffer so they can plan their reboot on their own terms.
Readme
Just download and install the .pkg, no configuration needed. Once a scheduled DDM update is deployed from your MDM, the menu bar icon will display the time remaining.