The development phase may cost more, but the USAF was looking at total program costs including estimated life-time operational costs... and apparently that last was where Boeing made up the difference and pulled ahead.
Funny... back years ago I was supporting Boeing, then I slowly was won over to the Euro side... and now am somewhat annoyed at this, but not really surprised.
Now the USAF needs to just do the smart thing and announce the non-competition, sole-source award of KC-Y (KC-135R replacement) to EADS.
Note that this was expected to total around 195 aircraft (15 per year 2024-2036), while KC-X (KC-135E replacement) is 175 production aircraft & 4 developmental aircraft.
Perhaps the balance can be adjusted to 200 KC-46A and 170 KC-45B (new competition, new variant letter), just to prevent any Boeing protests?
The KC-Z (KC-10 replacement) was expected to be in production starting in ~2036... that would be the next real competition (9 per year from 2037-2048, for ~108 total).