BSAL you said:-
"Does anyone know why there are two BMI Airbus aircraft parked at Dublin for a while now. One of them hasn't moved in 3 weeks I think its G-MIDS not sure though."
This is not correct - no BMI aircraft has been parked at Dublin for 3 weeks. As other replies suggest an A320 is occasionally parked on the west apron as a spare or between ad hoc charters.