If someone is going to stop using 2c8 Apps and you want to move their license to someone else, that is possible directly in 2c8 Portal. Navigate to Applications and select the application you want to move the license for. Hover over the user you want to remove the license from. On hover a more button will be displayed, this is the icon with three horizontal dots. Click the more button and select the option Remove from application. You will then be presented two different options, choose the option to Let another user take over the license. You can either assign the license to the new user right away or you can do it at a later time. In that case the license will be an unassigned license until you assign it to someone else. If you are wondering about the fee of moving a license, you can read more here.