Originally Posted by
Jasonation
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I found out that United will be adding four new upgrade-eligible fare classes for flights operated by Turkish Airlines.
This means that you can use the M, A, H, and S fares discounted coach tickets for a more affordable Turkish Airlines ticket.
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This presently reflected on UA's
Star Alliance Upgrade Awards
Strictly speaking, this is a TK change that is being reflected on UA's site. The operating airlines sets the upgradeable fare classes.