A few days ago someone posted in this forum about how Air India had changed his flight reservations on him. The same thing just happened to me on America West, for reservations held on October 20 for IAD-PHX. I had booked through American Express Platinum Travel Services and chosen America West Flight 35 from among many choices because the times were convenient and it is non-stop. The reservation was made in March and confirmed by American Express and America West.
I have just this morning received an email saying that America West has re-assigned me to a different flight that leaves IAD much later, requires a change in LAS, and gets into PHX past midnight. A 4+ hour nonstop flight has turned into a 7+ hour flight that requires a change, and messed up plans for business partners flying to PHX from different locations to arrive simultaneously with me at PHX.
I checked the America West web site and they are still offering tickets on Flight 35 for that particular day, so it's not that the flight has been taken off the schedules. I would have understood (although not liked) that situation, since I know airlines often make changes to their flight routes. No - they have just decided that they don't want to carry me on the flight for which they sold me the ticket, and have assigned me to a different flight combination.
Apparently this practice is not limited to Air India.