When OnePlaceMail or OnePlaceDocs is used for the first time, the users credentials will automatically be added to the OnePlace Solutions license list in SharePoint, and the user entries for 'OnePlaceMail' | 'OnePlaceDocs | and 'OnePlaceLive' will be added to the list.
If a user ceases to use and uninstalls the OnePlace Solution suite of products, their credentials can be removed from this list, freeing up a license for another user. This is not done automatically.