This clause illustrates the call flow for call progression for a Priority Service call with trunk queuing at the originating MSC but the Priority Service request times out of the trunk queue before a trunk becomes available.
If the trunk queuing timer expires before an idle trunk becomes available, the MSC/VLR removes the call from the outgoing trunk queue. The MSC/VLR then initiates call clearing by stopping all running CC timers, sending a Disconnect message to the MS with cause #34 "no circuit/channel available", and starting CC timer T305.
On receipt of the Release Complete message, the MS stops all running CC timers and releases the MM connection. The MSC/VLR indicates that the radio resource(s) should be released by sending a Clear Command message to the BSS with cause "Requested terrestrial resource unavailable".