The BHX-HHN flight was operated by an aircraft based in Spain (I've been on it a few times, Spanish crew and ads). So this is not linked to BHX in any way, but actually on a W pattern via HHN. HHN is also endured more cuts currently, not just to the UK, so who knows where this exact plane is going now, maybe Bari or so. Interesting that they keep BHX-NRN, that's somehow a niche. A bit odd how FR pushes so much into Italy and Spain, while both economies are really feeling the crises.
Looking at AirBaltic's recent development, things like RIX-FRA and frequent KUN-RIX with various connections, FR surely doesn't like that. They seem to get squeezed a bit by Wizzair and AirBaltic in Eastern Europe, also they haven't jumped yet at the vacated BTS opportunities, while FlyNiki doesn't sleep.