Using the CAA May figures and calculating load factor by RPK / ASK (which is technically the way it should be done, as opposed to seat-factor - so the figures are stage-length adjusted), you get:
Aurigny 64.9%
BA CityFlyer 72.9%
Blue Islands 66.2%
British Airways 78.9% (short-haul Airbus fleet only)
Eastern Airways 57.3%
easyJet UK 82.4%
Flybe 19.7%
Loganair 63.4%
Ryanair UK 77.6% (8 UK aircraft reported)
So you broadly have three groups - easyJet, BA and Ryanair at relatively high load factors (although below the sold seat factors they announce), then the UK regional operators all in a fairly narrow band between 57% and 66%, and then Flybe at 19%. I'm wondering if the figures are correct - they are so bad that it's hard to imagine. But the CAA only report the data that airlines submit to them, so if there is an error then the strong likelihood is it's from Flybe's own data.