EI BUD
The second scenario you describe of booking a one way with a stopover in London will be no more post 28 April as per the changes outlined today. No free UK connections so the price of say a return BHD-PRG will go from 9k avios + £35 to 18k avios and £70!
Surely this will impact on the loads from BHD. Maybe not in the short term - in fact they will probably increase in the short term as the current rates are bookable until 28 April to almost a year ahead - but as someone who used it quite a bit for flights to Europe it will be far too expensive to justify over LCCs. Maybe that's why Ryanair are sniffing about again!