From what I have heard it will not be a huge announcement from FR
I've heard that they are looking at STN and/or LGW and it will be BHD
Both will be done by either a STN aircraft flying into BHD similar to what EZY do into BFS in the mornings
and if LGW is done it will be a W pattern from DUB
FR know where their passengers travel from to use them, if people are happy to travel to DUB from NI and help them fill their flight, then FR is not going to come to their doorstep when they don't need to, to then worry about loads
Same situation on the transatlantic flight by EI from BFS. When they realised very quickly they didn't need to open up long haul flights from belfast when passengers where very happy to travel to dublin for them