BAH are also great when you have a flight time change which may impede your connection fulfillment. You can often end up with a better itinerary at no extra cost.
I had a break booked to Bologna EDI-LCY-LHR-BLQ outward.
The flight to LCY was changed to arrive at 1825 rather than 1730 leaving me just over 2 Hours to make my BLQ connection at LHR-dodgy to say the least.
Before I rang them I checked and there was an earlier flight from EDI to LCY at similar price to my new one that would facilitate a seamless changeover.
When I rang up she discounted that and insisted on changing me to a flight from EDI direct to LHR. I had looked at the prices for them but they were £100+ more than the LCY one.
Bearing in mind the whole break cost was just north of £300 this was an epic result. no traipse from LCY to LHR and a few bob saved.