Microsoft announced that Yammer and Office profiles will be merged. Until today a user gets provisioned and logs into Yammer. This triggers the “creation” of its Yammer profile which is synced from the user’s Office profile. However, if a user changes values of his/her Yammer profile it is overwritten by the next Office profile sync to Yammer in case the Office profile was changed.

What does this mean for my users?
Well, it means that the users’ profiles become one and will based of the Office profile. The Office profile becomes the “master” and sole profile.
So, the profile button in Yammer will disappear soon and than every profile value is based on the Office profile. Single profile instead.
How can you manage the merged Yammer/Office profiles of users?
Due to the fact that there will be only one profile left you’ll need to manage only the users’ Office profiles. Either a user can manage this within set limits on the Office 365 Delve profile page or by contacting your Office 365 administrator and support.
Conclusion, opinion and summary
To sum it up, you’ll manage user attributes via Active Directory. Either in you onpremise AD which is synced via AAD Connect to Azure AD and Office 365. Or in case you are cloud-native user attributes from Azure AD are used.
Depending on how much “self-serving” you allow users could make changes to the profile by using the Delve profile (page).