Updating VoiceAttack normally does not affect settings, profiles, or third-party plugins.
You should not need to redo anything, no.
You could make a backup of the installation directory, export your settings using the "Export Settings" button on the "System / Advanced" tab of the VoiceAttack options window, and use the "Click here to browse VoiceAttack's data folder." link on the same tab to open the directory containing the profile database and its backups, which you can make copies of in a safe location.
What that wouldn't account for is anything stored by third-party products outside of those locations.