The Secretary of State for Transport, Rt Hon Justine Greening MP, visited Birmingham Airport today to learn more about the huge capacity that is available immediately, and how Birmingham Airport can take pressure off creaking South East airports.
To be fair to JG, the above comes from a BHX Airport press release, not one from the DfT, so there's still some hope that the Department hasn't swallowed the sales pitch.
Yes, Birmingham will expand by gradually adding destinations, routes and airlines as time goes by, but to suggest that this will have any more than a negligible effect on demand/capacity in the southeast is nonsense.