AutoUpdatesEnabled (boolean): Whether automatic updates are enabled or not. If not, most of the following are N/A.
AutoUpdatesMandatory (boolean): Whether automatic updates are mandatory or not.
AutoUpdateNotificationLevel (string): Notification level, one of
Notify before download
Notify before installation
Notify at scheduled installation time
UpdateAgentStatus (string): Status of the service.
UpdateAgentVersion (string): Version number of the update service agent
LastSuccessfulDetect (string): Time of last successful detection
LastSuccessfulDownload (string): Time of last successful download
LastSuccessfulInstall (string): Time of last successful installation
NextDetectTime (string): Time of next scheduled detection.
HasPendingReboot (boolean): Whether a reboot is pending.
For Windows 10 and Window Server 2016 (and presumably later) the LastSuccessfulDownload and NextDetectTime values are not available, and prior to Agent v3.3 nor were LastSuccessfulDetect and LastSuccessfulInstall. (Microsoft have removed some registry values from these O/Ss.)