Room calendar management in Exchange email system

In Exchange Management Console, -
Create a Room Mailbox.
If the room does not have an owner, then we can right-click on the Room mailbox and select 'Manage Full Access Permission'. We can add users or user groups.

If the room has an owner, then it is of no use to change anything within 'Manage Full Access Permission'. We have to go to the owner's Outlook. In Calendar, we right-click on the Room, and select 'Change Sharing Permissions'. Add users or user groups, and change permissions.