I am reminded on when I first joined AFF. I used to think these people speak a different language. J,Y,B, Silver, Gold, SC, what the?
So now I have this link on my desktop. Travel class - Wikipedia, the free encyclopedia
And below is a copy from this site.
Business class codes
C, J, D, I, Z
On many airlines, C or J indicate full fare business class, whereas discounted and thus restricted and typically non-upgradeable fares are represented by D, I or Z. The codes in short:
C, J = Full-fare Business Class,
D, I, Z = Business Class Discounted,
(a lowercase "n" after any class code indicates Night Service)
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