It's much easier to simply use this with whatever date you prefer:

    defaults write com.apple.SoftwareUpdate MajorOSUserNotificationDate -date "2030-03-03 12:00:00 +0000"

▲ egb 4 hours ago | parent [-]

I've got that in place and still get the Tahoe popups, so there's some other mechanism here.

	▲	testing22321 2 hours ago \| parent [-]
		Same for me. I setup a focus for do not disturb that runs from 12am to 11:59pm every Day. Have not seen the popup on 4 weeks since I set it up