By default when you install Office (365 or 201x) it joins the ‘monthly’ update channel where you will receive all updates, both security and feature, as soon as they are released by Microsoft. Generally having the security updates applied immediately is a good thing, the feature/functionality updates on the other hand have had a tendency to break things on occasion. These issues have been resolved fairly quickly in most cases but to avoid any potential issues you can move your Click-to-Run install over to the slightly more pedestrian ‘semi-annual’ channel where you will still receive security updates in a timely manner but the functionality changes will only appear slowly and (hopefully) when any bugs have been ironed out.
To switch to the semi-annual channel, open an administrative command prompt and run the following commands:
cd C:\Program Files\Common Files\Microsoft Shared\ClickToRun
OfficeC2RClient.exe /changesetting Channel=Deferred
OfficeC2RClient.exe /update user
If you administer Microsoft 365 for your users via the portal, and allow them to download the Office suite when they sign in to office.com, you can define which version of Office is offered via the 365 admin center:
Show all | Settings | Org settings | Services | Office software download settings
Select the ‘Every six months (Semi-Annual Channel’ radio button