I have not travelled through BHX in ages, so my excuses for this question:
Is it possible to do an airside transfer when arriving from Dublin and connecting on a domestic flight? Or are passengers arriving in a separate arrival lounge and need to clear security again from landside if they are connecting (it would be a "self-built" connection, hebce the asking).
The last time I made a connection at BHX was when BA still had its Eurohub...