I am so not a winter competitor! I planned my warm up to take right up until just before the race. My husband was there to take my jogging pants. I was hydrated. I was cold, but I as ready. Sort of. I was about 1/3 of the way back in the group of runners waiting, when I noticed up front that a group had taken off. I asked who that was, and it was my race, the 10K! So I ran to the front and through the group of 5K runners in order to catch up. I ended up trying to pass dozens of slower runners and even the sleigh and reindeer runners! Not a good beginning, and not a good pace. I did finish; my time was not what I wanted, but I was in the middle of my age group.
What have I learned? Don't listen for an announcement. Don't expect a starter to fire a gun. Ask, and act! I don't ever want to be "running later" again!