The most common method of deploying Office from Office 365 subscriptions is via the Office 365 portal. To do so you select the Cog in the top right and from the menu that appears you select Office 365 settings.
From the options that appear on the left you select Software.
You then see Office 2013 and you select the Install button to kick off the Click to Run install.
BUT, if the tenant has the First Release option enabled and you scroll down a bit you’ll see that you also have the option to install the Office 2016 Preview!
Potential issue here is that if an end user decides to install the Office 2016 Preview then it REPLACES the existing Office 2013 (i.e. no side by side install).
Now Office 2016 is not currently supported by Microsoft (as it says) which may mean it is not a good idea for an organisation.
Problem is, I can’t see how to disable this option for end users without turning off First Release (which would remove other features you may want) or disabling Office installs completely. Hopefully, there is a PowerShell command or some option I have overlooked that allows administrators to disable the option for installing Office 2016 Preview. I understand that people on the First Release program want to see the new stuff BUT not sure whether administrators want their users running Office 2016 just yet! At least until it is out of preview. If you know how to disable the Office 2016 Preview option without disabling First Release or Office downloads in general I’d love to hear.
Update – I spoke too soon (the ability to control which users get first release features is rolling out as we speak. More in my updated blog post).