software update

I doubt there could be one. Because upgrade involves backups, pre-snapshots, image installation on slot, reboot, license re-activation, reload config etc, post-snapshot. Also there would be time when you'd encounter issues during upgrade.

Also when you do upgrade, there's high possibility your config would change based on versions, so you'd need to manually come up with multiple scripts to validate if your old setup and new setup configs are same and UP & running.