IAG has just bought 31 new Airbus a/c most of which are destined for Iberia, also with their acquisition of Air Lingus in 10 days time with the potential of another major hub (pre cleared US flights in Dublin?) then LHR can be juggled without the extra capacity some say BA need, I still think Northolt as a domestic satellite
could be a short term answer.
This is where WW is coming from why get involved in the enormous disruption and extra imposed costs of R3. Ryanair does it successfully by switching when local authorities get tough, so why can't Willy?.