How to remove/reset to factory Ubuntu in Windows 10 Insider Preview 14316

I installed the Ubuntu subsystem on Windows 10 Insider Preview 14316. Now I would like to remove it or, better, revert to its factory defaults i.e. as it was when just installed.

I tried to remove it from the "Tu Windows features on or off" windows, with no luck. I tried to mark it as "off" in the above windows and delete its files manually (%USERPROFILE%/AppData/Local/lxss), with no luck.

Anyone succeeded in removing/resetting to factory the Ubuntu subsystem?