Weren't the Z fares just the holiday promos to try to fill the biz cabins when business travelers stay home over Xmas? I recall that AA had all of Europe on sale from SFO over Xmas for $1799 in I class, which is their equivalent of Z class. But UA didn't drop that low this past holiday season. In 2002/2003 season, they were $1199, and UA matched!
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