Yesterday Microsoft has introduced a feature within Office groups to set an expiry date. What does this means.
This means that you can set a 30 days expiration of a group. When the experation date is passed the owner of the group gets a notification to renew the expiration date for another 30 days or even more.
You can set the expiration of Office groups in Azure Active directory.
When you’re not setting a new expiration date the group will be removed and put into soft deleted.
See my post How to restore a group on how to restore a office group.