To be honest, SE is being disingenuous here. They knew they wanted to flying well before 3.0, obviously. Why did they not simply redesign the 2.0 zones back then? They could have actually started small, maybe one zone a patch, or whatever. The players would not have even know since the redesign would only have affected things we couldn't see anyway.

If they had done even half of a zone each major patch since 3.0, which could have been done concurrently with everything else... they'd be done by now, or at least well into having it ready by 4.0 without delaying anything. it's not a zero-sum game.