How do I prevent my Monterey 12.2.1 USB installer from auto-updating the OS during install?

Created a Monterey 12.2.1 USB installer as per Apple official instructions using createinstallmedia in Terminal. So to test if the installer works, I created a new volume on my internal drive and installed. And it did something BigTime irritating. It updated the OS to 12.3.1 automatically during installation. This is NOT the goal. So spouse suggested that I turn off all access to the internet and try again. Found a tiny little Wifi icon in the Recovery window and turned it off, and then ran the USB installer again on a second newly created empty internal volume. But this time it failed: "An internet connection is required to install macOS." How can I prevent them from updating the OS during install? The USB installer was created in Terminal. Is there a Terminal command to add to guarantee that it stays at Monterey 12.2.1 as created?

Followed these instructions and downloaded Monterey from the link provided. It gave me Monterey 12.2.1 at the time.

How to create a bootable installer for macOS - Apple Support