There was a flight in the small hours of this morning that woke me up. It must have been either landing at or taking off from Bristol but I've no idea where it was going/from.
The last departure last night was Ryanair to Dublin, at 2212. That was all that was shown until the same flight tonight. there may be the occasional private flight. They usually happen before midnight, though. It wasn't Sir James so far as I can tell.
Reminds me of my return flight from a holiday in Limassol, Cyprus in July 2009. Loadings must have been a bit light because the two flights from Larnaca to Bournemouth and Gatwick that day were amalgamated into one calling at Bournemouth first then Gatwick. I remember there being quite a wait between landing and taking off again.
Checking distances, as the crow flies it's about 76 miles but the flight miles would have been longer.
There are a number of things that can affect aircraft turnaround. One is refuelling - I doubt you would do that for a short hop. The pilot would have uplifted enough for both take-offs and flights. Passenger unloading and loading is another, but presumably that would be one-way traffic at Bournemouth, with the the cases for the first drop by the door of the cargo hold, separate from the Gatwick stuff.
Another consideration that isn't usually noticed, but is very much on the mind of the pilot, is brake cooling. They get pretty hot on landing, with 400°C not being unusual. They have to be down to 100°C to 150°C before starting to taxy depending on the type, to make sure that they work efficiently in the event of a rejected take-off. Usually, the normal 40 minute turnaround for an A320 or B737 is enough, particularly on a decent length runway like Bournemouth with a light load on a nice day, when the autobraking would have been set to low, but it does mean you can't land, chuck out the pax, and take off straight away. Airbus, and I assume others, have a temperate gauge and a countdown on the control panel to time needed to brakes being usable again, There are fans, but there are reasons why these are not often used, and they don't speed it up much in any case. And there is always the need to get a slot through all the traffic then into Gatwick - you wouldn't want to take of for a 70 nm flight and have to stack for an hour.