I've just seen an entire thread on issues regarding DL interpreting the first letter of the fare basis code as the booking code for crediting AM flights, which seems to be a problem when one has to manually request for credit.

So this has me concerned: I've searched on the ITA Matrix for my upcoming mileage run on VS: JFK-LHR-JNB on an Economy Delight (V) fare (also indicated on all 4 segments on the reservation page) which earns me about 25% MQDs and 125% MQMs, the fare basis code for the outbound is "NKRP0SCN" and inbound "OKRP0SCN." I really hate to see if it's interpreted as an (N) and (O) fare, which only earns 5% MQDs.

I've checked the business fare (I) on VS on another flight, and it corresponds to the first letter of the fare basis code. This inconsistency adds more to my concern.

So just inquiring anyone's experiences regarding postings from VS flights, especially if DL credits VS flights in the wrong booking class or no automatic postings at all, specifically in Economy Delight. I've experienced both of these from Aeromexico when booked on an (I) fare but credited as an (N) fare as it is the first letter of the fare basis code, and I don't want to go through the same struggle with Virgin Atlantic again.

In my experience (having been screwed by those AM fares), VS posts more consistently than AM and their fares have coded correctly for me. I would just advise against using a GUC on economy fares, as this will convert you to their award fare class, and you'll be forced to request the credit manually. This is what causes the most problems.

I've flown VS Economy Delight a number of times. It will credit correctly and booking class will be 'V'. VS uses coach fare basis codes for Economy Delight fares just like DL uses for C+ and BE fares. The second to last character in the fare basis code is a 'C' which means you have an Economy Delight fare (they also use 'I') that books into V. DL C+ fares will also have a C or I as second to last character in fare basis code and book into DL W and S classes. There is a dual inventory check on these fares. There must be inventory in both the booking class and underlying coach class from first letter of fare basis code. It enables them to have a range of fares for Economy Delight, C+, and BE (corresponding to the various main cabin fares) while only having one or two booking classes to work with (as there are only so many letters in the alphabet).

DL should be going by the fare class the ticket shows. Generally the issues I've seen are when an agent must manually give credit. They then look at fare basis ignoring the fact this may not be the actual booking code. Most non main cabin fares use a dual inventory check to ensure C+ or F doesn't cost less than main cabin. The first letter is the main cabin class, not the booking class.

Has anyone successfully argued and won a Delta debate over fare class vs fare basis? I just flew VS on what should have been credited as V but they are saying fare basis was M. I am more than frustrated with Delta right now. What are my means of turning this given the SM department apparently does not communicate with the public?

Haven't had any issues with VS Economy Delight fares posting correctly over the years. Do you have email receipt from VS showing Economy Delight V booking class fare (like below)? Note that fare basis and booking class are not the same. The 8 letter fare basis code on VS Economy Delight fares will start with a coach class basis, but will have V booking class (this is part of dual inventory checking for such fares). The second to last letter of Economy Delight fares will be a C in fare basis code. Unfortunately, VS doesn't not include fare basis codes in email receipts like DL does.

Does anyone know if I book Economy Classic and then upgrade with cash on the VS web site to Economy Delight, will that change the fare to V, and will DL credit me as if I purchased a V fare?