Wasn't VLM's LCY-JER/IOM more or less a parking exercise, with the aircraft operating to the islands after early morning cross-channel runs at off-peak times and spending hours on the round at IOM and JER before being brought back to LCY on the afternoon.
That said, flight timings were not exactly great and did, of course, not allow day returns. However, it must be said that VLM initially operated like three flights a day to JER and could not make them work. I am not sure if that was all because of their non-alignment to one of the alliances (they have done nicely for 15 years on many LCY routes)