I figured it was because a team didn't start or something. Don't they usually have more than 11? Disappointing anyway, kinda makes the first leg not matter.
edit: never mind, looks like since season 16 they have had 11.
https://en.wikipedia.org/wiki/The_Am...._TV_series%29
They didn't get a non-elimination penalty though, which I think has not happened in a long time.