My official stats are now up:
total time = 1.23.37
121st out of about 190.
15:54 swim (128th overall)
39.01 cycle (123rd overall)
25.26 run (115th overall)
I'm quite encouraged. The swim time includes the time it took me to take off the wetsuit and get onto my bike, and can definitely be improved, and I think with more time to get used to the bike and a bit more training, I can improve the cycle and the run times too.
I've also contacted the guy who runs the local tri club, and I'm going to get some proper open water sessions in before London. Hopefully that will help me improve my technique and build up my confidence so I don't have a panic attack on the big day.
As this one was half the distance of London, I reckon that means I could be looking at a sub-3hour time for the full Olympic distance, which is both pleasing and daunting all at the same time.