upmarket holiday companies Corsican Places and a few others charter their own flights for a shortish summer season from LHR LGW the regionals
BRS for example is op'd by a BMI on a 49 seat EMBR and STN by Titan 733 although they sub out often
they fly to Bastia Figari and Calvi
LHR Corsica and Sardinia charters are also offered flying with BA
(you will be surprised how many charters BA operates now at weekends from LHR - huge programme)
Calvi Bastia Figari Olbia and Cagliari
plus many Greek islands and a weekly Cunard Line cruise charter on a B767 to VCE/Trieste BCN ATH and FCO