Cathay Pacific Asia Miles - Upgrading Fare Basis on CX?

Apologies if this is the wrong forum, but -
I'm traveling to Japan and Korea on business the last week in September. Per Expedia, over the weekend I could include a run to SIN on CX at virtually no cost. However, the CX flights are coming up as S or M class, not at a qualifying fare (B, H or Y). The Expedia people have no idea what it would cost to upgrade those legs unless I go ahead and book the tix. Catch-22 though - I don't want to book the SIN itinerary if the upgrade cost is ridiculous. Here's the itinerary:

9/23 SJC-DFW-NRT on AA2442/AA175
9/28 NRT-HKG-SIN, CX509/711
9/29 SIN-HKG-xTPE-ICN, CX710/420
10/1 ICN-KIX, OZ118
10/5 KIX-xHaneda/HRT-SJC, JL342/AA128

Total cost: $1290

Anyone have even a very rough estimate on what it would cost to upgrade the CX flights to B/H/Y? If I could do this (and change the return through DFW as well), it will put me a long way towards making EXP.

Joint fares are set by airlines. The booking classes are set by them in accordance to how much they will get paid as per apex paid fare.

You cannot just change the onward booking classes on CX from whatever it is set by the rules on that fare to another booking class just because it earns miles for you on AAdvantage. Pity, because for Asiamiles members, one will get miles for all legs on your itinerary including OZ and JL!

It will change the entire fare structure and you will end up paying a Y fare and you can see how much that will cost...ie over $4K.



[This message has been edited by Guy Betsy (edited 08-21-2002).]