Narrative:

Upon receipt of initial oceanic clearance; I reviewed the message along with the captain and accepted via cpdlc with czqx; it was rejected almost immediately and then a 2nd message arrived within about 5 seconds that appeared the same as the first; so it was re-accepted. It seemed as though it was a system anomaly but in fact had a change from FL380 to FL390 for crossing. No ATC verbal 'amendment to clearance' was given as is usually the case. About this time we did crew change. I was told after break that the FL390 was noticed by gander domestic prior to track entry and we entered track correctly so the system checks worked fine.

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Original NASA ASRS Text

Title: B777 flight crew reported receiving two oceanic clearances within five seconds from Gander and accepted both. A flight level change was assigned with the second clearance which the crew did not detect. Reportedly; their HF radio could transmit; but not receive.

Narrative: Upon receipt of initial oceanic clearance; I reviewed the message along with the captain and accepted via CPDLC with CZQX; it was rejected almost immediately and then a 2nd message arrived within about 5 seconds that appeared the same as the first; so it was re-accepted. It seemed as though it was a system anomaly but in fact had a change from FL380 to FL390 for crossing. No ATC verbal 'amendment to clearance' was given as is usually the case. About this time we did crew change. I was told after break that the FL390 was noticed by Gander domestic prior to track entry and we entered track correctly so the system checks worked fine.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.