Force macOS updates

Try this:

sudo defaults write /Library/Preferences/com.apple.SoftwareUpdate.plist AutomaticallyInstallMacOSUpdates -bool YES

Note:

Here is a neat little trick to figure these things out. That is how I found the answer above.

1) Keep the relevant Preferences folder open, and sorted by Date Modified, to see which files change.

2) Make the appropriate changes to the Settings

3) Open a copy of the relevant plist and see what it contains (by default, it opens in XCode):

-michal wrote:

thank you, so this way I can check almost all the changes I made?

Yes, most of them - that is, those that are directly associated with plist files.

That is how I find answers to questions like yours. However, some seem to be stored in some other places, and for those I do not know how to find the answer. Just today, there was some other thread (sorry, can't remember which one), where I hoped a similar trick would work, but I kept making the changes and there was not a plist file that could be associated with it. But when it does, this works nicely.