softwareupdate change behavior in Big Sur

I have a daemon that can check for and install software updates using softwareupdate. Up to Catalina 10.15.6, the order is

Code Block
softwareupdate --list
for each update {
softwareupdate --download
softwareupdate --install
}
if any update has Action == restart
restart

The above has worked so far, but starting with Big Sur beta 5, I was getting infinite loop of download, install, restart.

After some trial & error, it appears that in Big Sur whenever Action is 'restart', the --install has to be paired with --restart. For example, updating from beta 6 to beta 7 would be

Code Block
softwareupdate --install "macOS Big Sur Beta 7-20A5374g" --restart


This is not consistent with softwareupdate's man page, which has not been updated since 2012.

Anyone else notice this change? I don't know if the pairing --install/--restart is intentional because of the new Update volume, or is a bug that will go away soon. I already files a bug regarding this, FB8700934.

softwareupdate change behavior in Big Sur
 
 
Q