Based on the continuity support of the outgoing channel selected, MGCF sends a IAM or COT message
to the CS Networks. In case the outgoing channel supports continuity indication, MGCF has already
sent out the IAM message, and at this point sends out a COT message.
The CS Networks establishes the path to the destination. In the present case the CS Networks responds
with an ACM message containing a "subscriber free" indication, implying that the called party is being