JanSmartist,
You're welcome, it's always our pleasure to help.
Regarding automatic updates within macOS, this feature helps to install new updates to the particular macOS version you're using. For example, it'll install macOS 10.15.7 automatically if you're using macOS 10.15.4. However, upgrades will be separate, and provide an overhaul to the system. These would need to be manually upgraded to. An example of an upgrade to macOS (rather than an update) would be an upgrade from macOS Catalina to macOS Big Sur.
We hope that helps to clarify.
Take care.