mjd1988
Guru
Well that's strange. It certainly said 50km when I signed up, then stopped at 25. There was a counter in the centre of the screen at the bottom, as there usually is at the end of a training session, so that must have been saving data at the end of the race. Coming towards the end there were a few people behind me, but I guess some of them dropped out before the line.
They probably didn't drop out - Zwiftpower filter out people who have unrealistic results, or no heart rate monitor so you'll often find that you finish higher on it and there are less people behind you, so if you finish 15/40 on the zwift results you wouldn't be too surprised to look on zwiftpower and find you've been upgraded to 6/22 or something.
I've never been in a race that was shortened (that i know of) so that is a bit weird - there is a bar near the top of the screen that tells you how much distance you usually have left so you know when to sprint.