Upgrades show the currently available upgrades if any. If upgrades are available, an upgrade can be started by pressing the Upgrade button at the top under Status.
To see changes see the Changelog
After the upgrade begins, it will download the new packages (which may take some time) and then the upgrades will be applied. Do not reboot or power off the server during the upgrade.
If Automatically Install Upgrades is checked, Untangle will automatically check for new versions and upgrade if available.
Automatic Upgrade Schedule configures when Untangle will automatically upgrade if upgrades are available. Untangle will automatically upgrade at the specified time on the days of the week than are checked.