macOS Mojave 10.14.x Update Preferences – Default Writes

Automatic check for updates
[cc]sudo defaults write /Library/Preferences/com.apple.SoftwareUpdate AutomaticCheckEnabled -bool TRUE[/cc]

Automatic download new updates when available
[cc]sudo defaults write /Library/Preferences/com.apple.SoftwareUpdate AutomaticDownload -boolean TRUE[/cc]

Install macOS updates
[cc]sudo defaults write /Library/Preferences/com.apple.SoftwareUpdate AutomaticallyInstallMacOSUpdates -boolean TRUE[/cc]

Install app updates from the App Store
[cc]sudo defaults write /Library/Preferences/com.apple.commerce AutoUpdate -bool TRUE[/cc]

Install System Data Files and Security Updates (both writes required)
[cc]sudo defaults write /Library/Preferences/com.apple.SoftwareUpdate CriticalUpdateInstall -boolean TRUE[/cc]
[cc]sudo defaults write /Library/Preferences/com.apple.SoftwareUpdate ConfigDataInstall -boolean TRUE[/cc]