As far as I can tell, the update is passive and done in the background. My System Information profile shows that it was done at a time and day (2/28) when my computer was awake, but I did not do the installation.
On a Mac since 1984. Currently: 24" M1 iMac, M2 Pro Mac mini with 27" BenQ monitor, M2 Macbook Air, MacOS 14.x; iPhones, iPods (yes, still) and iPads.
