Who said it HAD to be domestic? INV would probably not fill a 737 (not even a -500) from BHX. Then again, if it does turn out to be domestic, why not JER - to turn the heat on Flybe?
What BHX needs (apart from a takeover by BAA
) is a number of NEW routes (ex: Central Europe, Baltic States, Balkans, Austria, etc)
Cheers