I agree that changing the ranking methodology after the competition ended and quietly moving ningjia from 4th to 5th place is unfair. This contradicts the earlier communication that Phase 2 would be based on the combined test set.
Rather than modifying ranking rules post-competition, I suggest expanding 3rd Place from 2 winners to 3 winners to fairly recognize all deserving teams. This would be more transparent and equitable than retroactive rule changes.
The competition should maintain the integrity established during the actual competition period.