Be very wary of airfields like Exeter who are promulgated open until early morning. Acceptance of movements is PPR only after a certain time, plus you may find yourself incurring additional charges. I would have a read of the UK AIP pages that refer to opening hours before commiting yourself.
Bournemouth is a case in point - their hours are published as being 0630-2130 local, yet we receive and send a mail flight to them in the couple of hours bracketing midnight. You might find yourself unwelcome after the published hours though.
Surprised nobody's mentioned East Midlands - very H24!