MacOS Automatic Update or Manually

Personally.

If I what the Full Version of whatever.

Handy as I have 3 machines each currently with Sequoia 15.3.1

Download the Full Version on one machine and Stop there

Copy the " Install Sequoia app " to reliable External Drive

Copy back to Applications folder on the other 2 machines and " Bob's your Uncle " ready to install from 1 Download for 3 machines

Use the Terminal command line

softwareupdate --fetch-full-installer --full-installer-version 14.7.4

softwareupdate --fetch-full-installer --full-installer-version 15.3.1

I exclusively use Software Update and never automatically install updates other than the installation of Security Responses and system files. Software update maintains a history and downloading from CDN servers probably does not update the Software Update history and could potentially confuse it.

You are welcome

The only benefit might be

The Full Version is One Hand

Though, during the actually installation process.

The machine requires and active and stable Internet connection incase there are EFI Boot ROM specific to that machine is still be downloaded

Never had any issues using the software update menu.