Microsoft always sells the current versions of their products and services. However, you can get a Product Key and Installation Files for the previous versions using the Downgrade rights. Downgrade rights is a benefit available in Volume Licensing channel. Downgrade rights allow you to obtain a License in any version that Microsoft continues to make available for download through the Volume Licensing Service Center. For example, with Windows Server, you can choose to download the 2016, 2012 R2, or 2012 versions of the edition you've licensed. Downgrading does not depend on Software Assurance; it is a benefit of Volume Licensing. Please check the Microsoft Downgrade Rights Licensing Brief here: http://download.microsoft.com/download/6/8/9/68964284-864d-4a6d-aed9-f2c1f8f23e14/Downgrade_Rights.pdf
2018-09-07