I did exactly that in response to a Upgrade to Sonoma alert (“X” button to dismiss the notification.) Walked away from my computer came back and an alert "
“Restarting Your Computer
Your computer needs to restart to
install updates”
I found multiple references to this file in install.log: “MSU_UPDATE_23C71_patch_14.2.1”
However I can’t find it. Clearly if I restart I’m screwed. Anyone knew how to stop it at this point? I’m running Monterey. I’ve already backed out Sonoma once. It was a major PITA!