"Just my two cents worth and maybe something investigators could consider. Criticise all you like but this happened to me when I converted from AirbusA330 to the 777. ( fortunately in the sim) it may be relevant as the trainee on this flight previously flew a320'and may well have been converting from Airbus to Boeing."
From what I have read so far I had the impression he was in the transition from B744 to B772. But that are only my 2 cents :-).