Thanks serfty and Viajero. Good news about LGW & LHR being regarded as the same (w.r.t. transfer status). Too bad that BA no longer pay for the b*s ride between the two (GBP14 iirc?). Looks like a rental car and sightseeing is the way to go.

I do like the "free insurance" reference to having flight info on the ticket instead of OPEN. Some of my proposed routes early in the trip are already only operated 3 or 4 days per week - so there is always the chance they may go to zero days per week - which would require re-issue if OPEN dated.