This policy setting allows you to specify a version number that you want to update Office to. For example, version 15.0.4551.1512.If ...

This policy setting allows you to specify a version number that you want to update Office to.  For example, version 15.0.4551.1512.If you enable this policy setting, you specify the version that you want to update Office to. The next time Office looks for updates, Office will try to update to that version. The version must be available where Office is configured to look for updates (for example, on a network share). If you enable this policy setting, but you leave the version blank, Office is updated to the most current version that's available at the update location for Office.If you disable or don't configure this policy setting, Office is updated to the most current version that's available at the update location for Office, unless you specify a different version by using the Office Deployment Tool.Important:  This policy setting only applies to Office products that are installed by using Click-to-Run. It doesn't apply to Office products that use Windows Installer (MSI).