Originally Posted by
vexorg
The letter may have no "meaning", but there will be a set of conditions attached for KLM/air france. Ok..... if I must spell it out
What are the conditions for fare class J?
What are the conditions for fare class C?
What are the conditions for fare class D?
What are the conditions for fare class I?
What are the conditions for fare class Z?
What are the conditions for fare class Y?
...
...
Getting a bit tedius, but do I need to list every letter, or can we get the idea now?
Sorry vexorg, but it seems that you did not read or understand the replies you got.
A question such as "what are the conditions for class D?" Makes no sense.
The one-letter fare bucket is only meaningful in terms of seat availability. But the fare conditions depend on the precise fare code such as (invented) D9HKGX. There can be many such fares within the D bucket, I.e. with a fare code starting with the letter D. And the fare conditions vary across D fares and across countries. A given D***** fare might or might not be available at a given time and conditions vary over time and across countries. There can be several fares starting with D available at a given time, each with different conditions. But you can book them ONLY if there is seat availability in the D fare bucket.
To try to summarize: the ticket class can only be either first, business, premium Eco or economy. The seat availability is per fare bucket (single letter). The fare conditions are specific to each ticket code (6 or 8 letters/numbers) not to a fare bucket (one letter).