Take a look at Veronika McKillop’s slide to help us understand why her teams at Microsoft are moving to IPv6 Only networks for Internal IT use.
Microsoft currently has two test IPv6-Only networks in Redmond, WA and also recognized that IPv6 adoption will be supported because of the well known “Microsoft effect” which posits that 85% of global laptop/desktops are windows based IPv6 capable coupled with the fact that millions of devices (ie: servers, Xbox, tables, HoloLens) are designed for IPv6 networks.