From time to time, new versions of addon scripts are released. These version may contain new features, security updates, etc. You can use cPanel to upgrade to the latest version of an addon that is installed on the server your site is hosted on.
To do so, click on the name of the addon. Then go down to Upgrade.
You can also set up automatic notification when new verisons of your addons become available. To do so, click on here on the main page of the Scripts Library. If you enable this option, the contact email for each addon will be notified when there is a newer version available than what is installed.