Join Date: May 2012
Location: MCO
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Posts: 12,810
On different routes then the numbers may vary and you may have more success with DTW than ATL. Statistically however, assuming you're on a 75X against a domestic 763:
75X: 26F against 158Y about 16.5%F
763: 30F against 231Y about 13.0%F
There's a slightly better chance on the 757. ATL may be tougher than DTW though, had a companion upgrade on DTW-SEA clear a few weeks ago on a 75X, granted it was a Saturday.