Hi Vijay
The rel reason Call Aban after first digit actuallt tell us that the call was flowing normally but was released due to system beace of any reason here we can say that it was routed to ann.
I have discussed thai thing and arrived at the following result:
The call is routed to ann after ending the ring back tone and it mentions the release cause as an unanswered call(REL is sent after the ann is played).
i have a doubt that whether the A side receives any message between the events ending the ring back tone and giving the ann.
In siemens an incept is created for the ann which sends the rel cause. Here it sends the release cause as unanswered call.
Do share your views if i am wrong and tell me if any message is sent as i have discussed.
Bye
Ashish