Just to follow up on what ClipperDelta said, the fences only exist for 5 years after a single operating certificate is achieved. So, all this will go away around 2015.

Also, I'm not sure what is to be considered a replacement for the 744, but in terms of seat count, the 77W is nearly identical.

I'm just curious (as has been pointed out on a.net) how they define "direct replacement." I mean, we already know DL is looking at ditching the early 787s in favor of 77Ls. Does that mean the 787 fence includes the first 18 787s that arrive on property (which might be much later than originally planned, if they ever even operate 18)? Or, say they take 10 77Ls and 8 787s, would those be in the "fence?"