Is there a source for this?
BA are said to have been most happy with the current setup of the summer weekend flights in general, not specific to BRS, but it appears on the face of it the operational setup of these flights has been a complete mess. Continual schedule changes, poor timings (mainly at BHX in the first year) and various delays/cancellation this year couldn't have done the routes any favours.
The purpose behind the routes is to utilise the aircraft during the weekends when there's no use for them at LCY. From what I know they weren't particularly bothered about getting exceptional performance, but at least utilising the aircraft rather than having them parked up.
I can't see why these routes wouldn't work, especially from BRS. AGP, PMI and IBZ are all very popular routes, even with FR and EZY's frequencies flights are often full. I'm sure there would be a market for people that would want to avoid the LC's and frequent flyers that would use BA specifically. A shame if this is true. I really can't see them expanding into the regions on business routes unless they wanted to kill off BM. LCY is the home fort.