It's quite amazing how Monarch manage to fit in all these flights with their A330's and A300's. The A330's, of which they only own 2, are used to operate some European and African routes (Banjul, Luxor and Sharm el Sheikh) as well as Caribbean and Sanford routes. Not only that but i can't imagine that LGW
-MLE direct could be operated by anything but an A330 (from their fleet). The A330's are almost always in service, you would very rarely see a MON
A330 parked up on a remote stand unused (unless its nightstopping etc). This is another reason why it is the only aircraft type in the fleet that hasn't got the new colours yet.
I'm not completely sure, but i imagine that the A300's would operate a lot of the Gatwick/Manchester to Male/Goa via Bahrain flights, as well as the Amritsar-Bahrain-East Midlands-Gatwick flights. They can also be seen operating a lot of high density short/medium haul routes.