I believe it is tied to the OS release: http://blogs.windows.com/windows/b/bloggingwindows/archive/2013/05/30/continuing-the-windows-8-vision-with-windows-8-1.a

I believe it is tied to the OS release: http://blogs.windows.com/windows/b/bloggingwindows/archive/2013/05/30/continuing-the-windows-8-vision-with-windows-8-1.aspx http://blogs.windows.com/windows/b/bloggingwindows/archive/2...