I say: Do you have copies of the publicly-published orbital elements which show satellite orbits being changed? These things can't be kept secret since many GPS receivers allow display of the orbit data.
Aviation Leak had an article on it 1 or 2 issues ago (2003/07/01 or thereabouts). The GPS operator did change satellite orbits to concentrate more satellites over Iraq, providing greater accuracy and redundency for US forces.
However, as the older satellites are not failing as fast as anticipated, there are currently more in orbit than required to provide published accuracy, so this did not affect accuracy elsewhere.
sPh