Given that 764ERs are not insured for transatlantic service, I can absolutely 100% guarantee that there was no 767-400ER in FRA
, unless it was on its pre-delivery RTW flight with Boeing - as part of the promotional tour.
The reason that the 767-300ERs (with BizElite) were flying to Honolulu for a time were because the 764s were still being fitted out with larger seats, for crew rest. The 763 already had these, and were insured for over-water ops. Thus, in order to fill the services, they used these aircraft.
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