I wish I was half as optimistic as you - I see the J-STARS fiasco
happening all over again. In that case, the DoD thought that they could
wait forever to order 707 airframes to use as E-8Bs. They ordered one
and Boeing told them to hurry up and order the others - or else. The
DoD didn't believe them and Boeing shut the 707 line down. Boeing
either refused to reopen it or quoted huge reopening costs - the end
result being that the DoD was stuck with the one white elephant E-8B
they had bought and no other airframes. The DoD ended up trading the
E-8B to Omega for a pile of worn-out 707-320Cs. The DoD then paid
Northrop Grumman a fortune to rebuild them so they could be used as
E-8Cs. Now, they are complaining that the JT3Ds on the aircraft are
getting very difficult to maintain, so they will have to reengine them.
They could have had new 707 airframes, with new CFM56 engines (ala'
the E-8B), if they had just done things right.

I also have trouble believing that the E-10 will be easily platform
independent. A lot of engineering goes into creating a system such as
the E-10. You can't just plug and play with a different airframe
without spending huge piles of money. And if they were going to move
from the 767-400ER airframe, what will they use? The bigger, longer
range 7E7 won't be available in time. The only choice will be used
767-400ERs. At least these will be younger than the 707s that the E-8Cs
were built from.