<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by andrzej:
but the 757s are everywhere.
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That's actually not entirely true. They are repositioning the 757s around January (when the MRTC will be discontinued on the A300 and 757) to do leisure routes primarily.
For example, right now you are seeing a mixture of 757s and 738s (and one 763) on ORD-LAX. In January, it will switch to all 738s (instead of the 757s).