diver69 - I didn't perhaps state what I meant very clearly.
However drawing on posts subsequent to my original post what I should have said was that the flight numbers (not the squawk) entered into Aer Arran aircraft mode S transponders were rarely updated.
I would therefore suggest that EI-REM is flying around Finland with RE231 still entered as the flight number in the mode S transponder.
Given my user name you can probably deduce that I near an airport frequented by Aer Arran aircraft so my views can be substantiated by many.