When you bought one Server license, you are limited to the use of the Exchange Plug-in for only one server (see article 'What is a Server license').
As a result, you can not simply move the server license to another domain name or IP address.
You need to buy a new license from our shop.
When you move your server frequently or when you need a solution for more than one client we can make you an offer for a 'Site license' (unlimited deployment).