I have recently installed the new Office 2021 (I absolutely refuse the concept of subscription software and hence do not use anything 365). At some point it produced a pop up inviting me to try the "new look", but at the moment the computer was not...
Office 2021, Project 2021 and Visio 2021 (both Professional and Standard) are now available to MSDN subscribers as of an hour ago. I'm going to see what they are like.
:-)
Source: Announcing August Insider update for Office 2016 for Office 365 - Microsoft Community
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