Hi @Edward Campbell ,
By using this Graph API endpoint https://graph.microsoft.com/v1.0/places/microsoft.graph.room/
we can only fetch all the rooms in the tenant as mentioned here and if we are making any changes to this room resource (updation,deletion) operations, typically it will 4 to 24 hours to reflect the changes via Places Graph API endpoint.
You can exclusively find this rooms in Exchange online admin center under Recipients->Resources
Hope this helps.
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