Hope this answers your question..
Note: The Windows XP Preview Program offered only Windows XP Professional. Test versions of Windows XP Professional expire after 180 days. After you install the WPP pre-release version of Windows XP on your machine, you can upgrade to the final version of Windows XP Professional only, not to the final version of Windows XP Home Edition. Migrating your computer to Windows XP Home Edition after installing the WPP will require a clean installation of the operating system.