Update: May 4, 2018. The release of the new guide will be delayed until Whonix 14 is completed.
Update: November 2, 2018. Whonix 14 is released. But, now there are upstream issues with enigmail and icedove, among other issues. Thus, the release is delayed further.
Update: December 18, 2018. Whonix 14 is currently going through a number of cosmetic and programatic changes. An update will be available shortly after the changes are complete.