How do I roll back to 8.1?

[Windows Central Question]

I am on the Fast Insider track, and I guess to get build 10572 I have to roll back to 8.1? How do I do that? Do I just do a factory reset?

 

[dugenhiser]

There is a program that you download from Microsoft.

Here is a how to

http://m.windowscentral.com/roll-back-windows-phone-81-windows-10-preview