The Windows Insider for IT Pro has been renamed to Windows Insider for Business.
You can sign up here: https://insider.windows.com/ForBusiness
The original announcement on Feb 15 2017 was teased here https://blogs.windows.com/windowsexperience/2017/02/15/making-windows-insider-program-better-pro-business-customers/#Vcx6fbmlyua62Wky.97
Now businesses can test their internal applications on the builds and patches before they are released. This is awesome to help increase the testing windows. Instead of waiting for patch tuesday test long before hand. Not only can you test and control who can test via GPOs you can see those results in the Windows Feedback Hub (WFH).
I will be posting a series of blogs about experience and usage!