So yesterday I was doing one of my periodic checks of my upcoming reservations on AA.com and noticed that a Oneworld Award that I had ticketed back in August was no longer displaying (a indication that there had been a schedule change). Sure enough, my final BA LHR-YYZ segment, while maintaining the same departure time and flight number had been downgraded from a 744 to a 763 and, as such, no longer featured a First Class cabin.

I was automatically rebooked in Club World, despite the fact that BA added a new 744 flight, departing a few hours later. Despite the fact that that flight was showing F3A2 on EF (a good indication that award seats aren't going to be available), there was a Z seat on the 744 flight, so I was able to change with no problem, but I was geared-up for a (polite) fight.

Is it the policy to keep a passenger on the same flight as originally booked even if that results in a downgrade when there is an alternative flight with the originally booked class of service?

If that is the policy, I don't like it. If I pay for First Class (and miles are a form of currency), I expect to be in First Class if it is offered. Ideally, I would have received a call about it and been offered the choice, but if that is not possible, I'd rather be moved to a flight with my originally selected calss of service.

What happens if award seats are no longer available in my class of service on the other flight?

I would expect AA to get me the seat and would not really care what they have to do to make it happen. As a last resort, I would expect them to allow me to reroute, even though doing so is not allowed under the rules for a Oneworld Award. Being forced into a downgrade is simply not an acceptable option.

I don't really care if that is an unreasonable position. After 120,000 flown miles, almost all on full fare RT J tickets this year (with another trip next month), I have earned the right to be unreasonable.