I noticed on Office 365 applications and the Office 2016 applications that there is an Autosave feature (which I believe was started in OneNote).
The official explanation of how the feature works (or rather what it is), according to the Microsoft site is as follows:
"Save early, save often" is now a thing of the past. Now there's AutoSave which saves every few seconds so that you don't have to.
AutoSave is enabled when a file is stored on OneDrive, OneDrive for Business, or SharePoint Online. It automatically saves your changes to the cloud as you are working. And, if other people are working on the same file, AutoSave lets them see your changes in a matter of seconds.
Having a mixed behaviour when it comes to saving seems to be an interesting behaviour, as generally you would think of an application having just a Save or AutoSave feature but not both.
Based on the explanation by Microsoft and how the UI is presented, is there potential confusion for the user or is the design clear enough to suggest how it will be used?