It's all over the news. The mediation board has not officially declared the impasse yet. The thirty day period starts after that. If they declare it by next week then it will screw up the holidays. However, there is no deadline, so that's still up the air.
After reading the flight attendants website it seems they do not want the same thing that all the other unions at USAirways get -- parity+one. I can't see how USAirways can give that union special treatment compared to their others so it doesn't look good.