A Clients Outlook Calendar had no option to set her Permission Level to Free/Busy time. For some reason, the default view was changed to Reviewer and any person that would try and schedule an event with her would be able to see full details of the event.Luckily, the fix was simple. It was a powershell command that reset it.
Set-MailboxFolderPermission -Identity someone@somecompany:Calendar -User Default -AccessRights AvailabilityOnly
Seemed to reset the default permissions, and then her account showed only the Free/Busy time and no details.