softwareupdate behaviour

I notice that when running softwareupdate --install with sudo on the DTK, we get the message not to run it with sudo on Apple Silicon Macs. When we run it without sudo, at the point of installation of the update, a GUI prompt appears asking for a password.

It's not clear from the prompt whether the account needs to be an administrator or not. there is only one field - no opportunity to provide a different user. Also, since we had to run through the update to test the behaviour, it's also not clear if running a software update from the GUI requires credentials.

Does anyone know if/where there is documentation about this change in behaviour? Or can share their experiences so we can piece together the new behaviour? e.g. does this mean it's no longer possible to script a software update?