They come and they go........
In the airside fire-station crew room is this amusing murial featuring characters of the "Simpsons" which has been hand painted on the wall. The staff religiously count down their tour of duty (which lasts 4 x months) by moving their individual pegs from the bottom of the painting around all the dots which represent a single day until they reach "home sweet home" at the top. When they reach this point they know they are close to returning to the UK!