Originally Posted by
MSPeconomist
DL's T&C say that, among other things, the upgrade rules can be changed at any time. It wouldn't be a stretch to declare that discounted corporate contract Y fares no longer count as FULL Y, with FULL Y being required for the early upgrades. Depending on who is doing domestic business travel on Y fares, some corporate travel managers could protest and renegotiate contracts or pick other airlines when their contracts with DL are up for renewal. However, some companies might not care that their employees are sitting in the back on deeply discounted Y fares that company policy requires for the refund ability, especially if higher level executives are permitted to buy FC.
This is incorrect. You are referring to the t&c of the Medallion program (and to a certain extent to the COC and the tariffs (fare rules)).
DL enters all manner of corporate contracts in which it commits to all manner of specific commitments and defines those as of a specified date. Those matter a great deal to companies which use those to do travel cost projections.
Unlike individuals who get the benefit of the Medallion program each day as it stands that day, large corporate customers cut deals which stand for a period of time. Not just as to the t&c of the FFP.