Add a Coexistence Mode - Only Calls in Skype for Business
We are in the journey from Skype for Business on-premise Enterprise Voice to Teams voice. We started by operating in Islands mode (because we didn't know any better/we wanted to introduce the full features of Teams to get buy-in). However, now that we are testing moving users to Teams Only with Phone System, we are finding that because all other users are in Islands mode, calls from the Teams Only users to users still using Skype Enterprise Voice are ringing to the Teams client, not to the users' desk phones or Skype client.
This can be solved by changing the Coexistence Mode to "Skype for Business with Teams Collaboration and Meetings," HOWEVER, this also completely removes the Chat section of Teams. This is HIGHLY undesirable, since we have been championing Teams as hard as we can. As an example, in order to test this I changed the Coexistence Mode of one of our internal IT staff, and she lost access to a group chat in which she had been planning a baby shower with a few other staff.
So, I believe I am requesting a new Coexistence Mode: "Skype for Business with Teams Collaboration, Meetings, and Chat" or perhaps "Teams with Skype for Business Calls." Referring to the diagram on https://4sysops.com/archives/understanding-microsoft-teams-coexistence-and-upgrade-modes/ This would be an additional Mode with Calls on the Skype for Business side and Chat, Meeting Schedule, and Teams and Channels on the Teams side.