A B767 ETOPS CARGO FLC HAS MOMENTS OF CONFUSION AS TO THE VALIDITY OF THEIR CLRNC RECEIVED FROM SHANWICK VIA ACARS; PRIOR TO THEIR COAST OUT POINT AT NIBOG INTXN; FO.

Narrative

WE REQUESTED OUR OCEANIC CLRNC VIA ACARS AND RECEIVED THE STANDARD MESSAGE; 'IF NO CLRNC RECEIVED WITHIN 20 MINS; REVERT TO VOICE PROCS.' APPROX 5 MINS LATER; WE RECEIVED OUR OCEANIC CLRNC VIA ACARS AT XA01Z. APPROX 10 MINS LATER; WE ACCEPTED THE CLRNC VIA ACARS. WE THOUGHT ALL WAS GOOD AND OUR OCEANIC CLRNC WAS RECEIVED (CLRED AS FILED). AT NIBOG (COAST OUT POINT); XA35Z; SHANWICK ON VHF READ OUR FULL RTE CLRNC WHEN WE CHKED IN. I READ IT ALL BACK AS WELL AS OUR OCEANIC CLRNC NUMBER. AT THIS POINT; I THOUGHT SHANWICK WAS CONFIRMING OUR CLRNC. APPROX 5 MINS LATER; WE CHKED IN ON HF WITH A SELCAL CHK. A FEW MINS LATER; SHANWICK SELCAL'ED US AND ASKED WHY WE IGNORED THE MESSAGE 'CALL SHANWICK BY VOICE.' THE 3 OF US DO NOT RECALL SEEING SUCH A MESSAGE (WHICH THEY SAID WAS SENT AT XA25Z) AND NO MESSAGES WERE STORED OTHER THAN THE WX/ETOPS OK MESSAGE. SHANWICK SAID IT WAS NOT A PROB BUT MAKE SURE TO ACKNOWLEDGE SUCH A MESSAGE (WHICH WE WOULD HAVE). ABOUT 10 MINS LATER; SHANWICK SELCAL'ED US AGAIN AND ASKED IF WE KNEW IT WAS MANDATORY TO ACKNOWLEDGE THAT MESSAGE. I TOLD THEM THE ONLY MESSAGE I RECALLED RECEIVING (OTHER THAN THE OCEANIC CLRNC) WAS THE 'IF NO CLRNC RECEIVED IN 20 MINS; REVERT TO VOICE PROCS;' BUT WE HAD OUR CLRNC. AGAIN; SHANWICK SAID NO PROB. AT THIS POINT; I ASKED SHANWICK IF WE NEEDED TO FILE A RPT AND THEY SAID NO. AFTER FURTHER DISCUSSION WITH MY CREW; WE DECIDED THERE WAS A MISCOM WITH SHANWICK AND QUITE POSSIBLY; SHANWICK THOUGHT WE WERE ABOUT TO COAST OUT WITHOUT AN OCEANIC CLRNC. I DECIDED TO CALL THEM ON HF A THIRD TIME AND EXPLAIN THAT AT XA11Z; WE HAD RECEIVED OUR OCEANIC CLRNC AND THAT WE ACCEPTED IT ABOUT 10 MINS LATER. AGAIN; SHANWICK SAID HE WOULD PASS THAT INFO ALONG BUT AGAIN STATED NO RPT WOULD BE FILED. I HAVE BEEN DOING OCEANIC XINGS FOR 16 OF MY LAST 19 YRS OF FLYING AND I KNOW NOT TO COAST OUT WITHOUT OCEANIC CLRNC. THIS IS MY FIRST XING IN WHICH I RECEIVED MY SHANWICK OCEANIC CLRNC VIA ACARS AND IN HINDSIGHT; FOUND IT SOMEWHAT CONFUSING. AFTER ACCEPTING THE CLRNC VIA THE 'ACCEPT' PROMPT; WE FELT AT THAT POINT WE HAD OUR OCEANIC CLRNC. IN THE FUTURE; I WILL CONTINUE TO CALL SHANWICK EVERY TIME WITH MY CLRNC NUMBER IN ORDER TO AVOID CONFUSION BTWN US AND SHANWICK.