Software Update Menu Bar
Designed for Declarative Device Management (DDM), SUMB gives IT admins complete control over macOS update reminders. Mix any combination of menu bar countdowns, native notifications, dock icon badges, and scheduled popups to suit your organization.
Readme
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. Requires macOS 15.0 or later. Apple Silicon or Intel.