If you have previously installed plugins and updates become available, you may see an “Update/s” notification in the Illustrator Plugins section of the Astute Manager.
You can update plugins individually by clicking on the Update button next to each plugin.
Alternatively:
You can either navigate to the Menu and select Update all plugins to update all plugins for the currently managed version of Adobe Illustrator.
Or, you can navigate to the Update Plugins page by clicking on the menu entry in the left-hand menu and again, opt to update plugins individually. From here, it's possible to see what each update provides.
Please note that if you have more than one version of Illustrator installed, you'll need to update your plugins for each version.