Indeed I have seen the ATC logs for that period (they still exist) and any outfit with a DC3, Rapide or Avro 19 seem to have flogged the route silly. The division between scheduled and charter is a bit woolly back then but the latter far outnumbered the former.
I heard a quote recently that during the 50's (I think!) that air traffic to the IOM counted for approx 50% of all UK movements...
From a look at the logs I would not doubt that statement. Absolutely fascinating documents of the period.