New sign-in experience for Office 365, what's it about?

Any idea how we disable this on our account? I tried it on my personal tennent and now at work when I try open a document either from the recently used list in office (in this case Word) or even from the 'Open in Word' option in Word online, I get the ususal popup to log in but before rednering the page it goes away and I get

This operation has been cancelled due to Admin restrictions...

Bascially it's trying to do something that Appsense (our App delivery here) doesn't like. I'm concerned users in the business might do the same thing.