[macro-dialout-trunk-predial-hook] exten ⇒ s,1,GotoIf($[«${OUT_${DIAL_TRUNK}:4:4}» = «A2B/»]?custom-freepbx-a2billing,${OUTNUM},1:2) exten ⇒ s,2,MacroExit

[custom-freepbx-a2billing] exten ⇒ _X.,1,DeadAGI(a2billing.php,${OUT_${DIAL_TRUNK}:8}) exten ⇒ _X.,n,Hangup()