An interesting question has come up in the Beta edit of Cairo. Harry and Julia catch a flight from London to Cairo, via Rome, on an augmented 707, ie a passenger jet based on the original design, but updated with the accelrated technology of the post-Transition 1950s.
One editor insists the 707 was already in service by the time of the story, approx 1954, to which I replied this is an augmented analog of that original design. Why not go up to a 737 then, he asked?
I don't think it's likely. I can see the Temps jumping to jet travel a lot quicker, and getting something like a 707 into the air well before it was due. But I don't see them being able to accelerate their technological base to the point where they can magic up advanced late 20th Century kit just because they've read a wikipedia entry. They're rocking 1970s miniaturisation in the 1950s, sure. But not 1990s.
Still, I will throw the debate open to the floor.