Thank you for your votes and comments on this, the team is planning out this work. We will update when we have more to share.
We are still considering the Voicemail on Busy feature for future releases, and will continue to update the status when it changes.
Note: The Busy on Busy feature has been released. Please see the following documentation for admin details:
An error occurred while saving the commentAnonymous commented
Hey Microsoft, What's happening here? are you working on it or not?
The team is working to address issues with call controls that occur for users running both Teams and Skype for Business. We will let you know when there is more to share.