When booking a "Resource" mailbox and setting as "busy" (i.e. "accepted") the resource mail box request may be sent to the opposite side to a requested attendee before the booking side has completely book the request. This results in a "Tentative" booking vs an "Accepted" booking.
The Calendar agent will then sync that "Tentative" status back to the other opposite side. Both sides may show a "Tentative" booking when it should show the room as "Busy" or already Accepted by attendees.
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