Welcome seb westerfield
And I will add my welcome to you, seb westerfield, welcome to Flyertalk and the British Airways board, it's good to see you here. This particular forum is the best place for anything BA or Avios related. If you have a look around some of the other posts, you will see you are not alone in sometimes finding it a frustrating experience. But patience and persistance tends to pay off in the end. Welcome on board.
I couldn't find any RJ availability either, not even on AMM to CAI, so it does suggest the feed of flights is kaput at the moment.