Sometimes an item is addressed to a group at your property:
When this happens, the Group Contact for that group is notified.
A Group Contact receives notifications for items addressed just to their group, not to a specific person in their group.
You can find the Group Contact for a group by looking under the group's name on its Group's Profile Page:
You can update a Group Contact for a group by adding or removing emails under Contact Info in a group's Group Profile Page.