Thanks for the suggestions. I tried London to Manchester (no reason for Manchester) and found a fare of ~U$160. Requires a Saturday-night stay but I had tried out-Saturday, back-Sunday.

I don't see Aer Lingus listed as a Oneworld partner anywhere. Are you sure?

But the point is a good one, I could fly to Spain on IB, or Finland on Finnair, and do it with a connection through an English city on BA. Or Edinburgh as you suggest, but connect through some other city on another European airline. While I'd love to visit Helsinki for a couple of nights (e.g.), I'd settle for a connection. If I spend too much time travelling, it will cut into my London time.

Guess I also have to make sure these cheap fares are all eligible for miles on CP and AA.

Thanks again!
andrew