we are trying to send SIP call to PBX with some logic as below.
Ext: 10001 to 10005
any call from the outside network goes on ext which is online and not busy at that time.
but if all user is busy i need clean 503 but i am getting 503 after 183 session progress.
please suggest how i can get clean 503 .
let me know if you need more information about the same.