We have announced that Group Owners will be able to leverage existing groups to drive membership in Office 365 Groups.
Same ETA question as everyone else, but in regards to GCC. Any chance this will be rolled out to everyone at once?
I'm amazed that this wasn't enabled from the outset, especially with how common it is now to replace desk phones with mobiles. I was able to update them using SharePointPnPPowerShellOnline, but it's a long process to loop through all users, and can't be automated. Hopefully we can figure out how to use a Microsoft Graph API, but I don't know yet if it'll work for our AAD license.
Has anybody had any luck with this?