Boeing not building extra a/c for best customer?

[JimNtexas]

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Also, in order to maximize efficencies in a new design, you will need to let go of the old ones. You can not keep the architecture the same and put new skin on it. ...

That's good point. Airbus tried to cobble together a collection of parts from other models to make the A350. Boeing's 787 strangled the A350 in the crib. Just this week Airbus announced that they are beginning a total redesign of this airplane, now called the A350WB. This airplane will be years late to the party.