Sorry to be a pain on this point, Ladies & Gents, but I really am confused.
Having taken a peek at FR's website I can only find 2 services ex EMA, both going to Spain (there may be others, but then I'm not terribly good with my PC.)
This means - assuming the a/c was flying south - that after 20mins, the flight would be in the area of the Channel. On the instructions of ATC it then returned to EMA, where, after coming on chocks, it was not disembarked for a further 30 mins. Then we run into the detention and all the other good stuff previously posted.
JUST HOW SERIOUS WAS THIS THREAT THAT ALLOWED AN A/C TO HAVE PEOPLE ON BOARD FOR THIS LENGTH OF TIME?