Hi, just thought I'd butt in.....as i was a rep there, you can fly to Athens,Thessoloniki or Dalaman(Turkey) then on to Rhodes out of season !
There are limited flights though (2 per week ?) Unless that has changed ?
There are no direct flights out of season.

P.S, you can fly to Dalaman then take a coach to Hisaranou(2hours) and get a ferry !