Originally Posted by
Utskicat
Nothing has changed on the website terms. You are looking at something outdated from years ago when this was true.

This is the current website:
https://www.delta.com/us/en/skymiles...llion-upgrades
Scroll down to "CURRENT ADDITIONAL UPGRADE CERTIFICATE POLICY TERMS & CONDITIONS", and you will see this text: "Valid on all KLM-marketed, KLM-operated flights from published Main Cabin fares in Y, B, or M class to Business Class."
Seems like inconsistent language...?