Word is back from one of the simulator developers on this:
Sorry to say what he reports is accurate. The race did actually run twice - simultaneously. Unluckily, he randomly managed to connect to the "wrong" one, otherwise this wouldn't have been noticed. He was the only one who connected to that race.
I'm very sorry that this happened. It's not the first time we have heard of something like this but it should be the last. We're going to work on a fix as soon as possible now that we understand the problem.
I've given you 100 reward points as compensation for any inconvenience this has caused you. Again, please accept our apologies. This was an extremely rare glitch related to the connection issues today, and we will be working on a solution for it.