macOS keeps updating even with only "check for updates" set

I can't figure out why macOS keeps updating itself without my consent. I have "automatically download" and "automatically update" turned off. But macOS is constantly indicating an update is available, and then on reboot, the new macOS installs itself anyways. Since this often tends to break Xcode or gpu capture, I'd really like to prevent this.

macOS keeps updating even with only "check for updates" set
 
 
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