you're right, X isn't (anymore ?) a revenue class on SA, though it is still shown in the GDS.

according to this thread, class W is for upgrades to business class.

OP updated. Where extra class has been added with unknown relative position I've put it at the low end.

Just got an upgrade to BC on SA.
It is I (used to be W, pre *A)

That thread pre-dates SA in *A. thijsseh is more up to date.

I notice a bunch of strange new codes for SA on KVS:
F P A U
C J Z D R
W is now an economy class with some other new ones.

The ones I've put in bold italic can't be award classes. Wonder what they are?

So it looks like SA is using the same fare buckets for awards and upgrades. Interesting. If that is true, then given that the ANA Mileage Club engine is reliably showing award availability for SA, one can use it to find upgrade availability! :cool: Must try that out.

D is being used for Star RTW bookings. SA is booking into Star Standard classes for the RTW products - A for First, D for Biz and M for Economy. H for Starlite/Star Special.

I must say this worries me a bit. If both an award and an upgrade are I fares, how will 'the system' know that I had an upgrade and debit me the miles I should get for buying an economy (S in my case) ticket :confused: . Especially important as I should get double miles as per the promotion. I guess I will find out soon, my trip is next week.

Lots of airlines use the same booking class for upgrades and awards. As long as they record the fare class separately (which they should do) then it all works out.

But no system is perfect and mistakes do happen - sometimes they are in pax favour and sometimes not requiring chase up.

Kiwi Flier can you mark the airlines that use the same class for Award and Upgrade, or should I assume that any airline without a separate, underlined, class uses a single class for both awards and upgrades?

Yes most use the same booking class for awards and upgrades. Known exceptions are noted.

J on OS
 

I just made a booking with OS and I got a business class in J
It says on their website J = Holiday Business.

Is this Class credited with the double mileage like C or D ?

Assuming (per your profile) that you are crediting to LH's M&M... then it is 200%, per this page.

Standby?
 

Not sure if this is an obvious thing, but it's something I haven't been able to find an answer for:

What booking classes are used for standby flights or are they the same classes as one would get for a regular booking? Specifically, I have a few days off coming up and want to go anywhere in the EU from DUB, but want to get the miles to get/keep status. So if I were to end up on a flight in (eg) BC, would I still get the miles for a J or C flight, or would it be some other, non-status class?

Most airlines appear to use the (sensible) rule that you get the miles for the class / fare that you PAID for, not the one that you travelled in. I am not sure what the situation is with what booking class is used for standby, I have always assumed (but this is untested) that a standby is a 'normal' booking class without availability. Interesting topic, I would like to understand this better!

Kiwi Flyer, could you please correct the SA codes. They are using O and I for upgrades as well as awards. (W was the old upgrade award.)