Demystifying Hybrid Free/Busy: Finding errors and troubleshooting

shameegunner12onmicr , if you are using Organization Relationship, and not IntraOrganization Connector, then we take the permission on Default user for userA in get-mailboxfolderpermission userA:\Calendar. And likely Default user is AvailabilityOnly in this case. If you change it here, then it would change for everyone.  If you would be using IntraOrganization Connector, then you could add the individual user in mailbox folder permission with reviewer permissions and it would work. Or with Org Relationship, technically with Calendar sharing invite then personal 1:1 sharing relationship would win over organization relationship.