Originally Posted by HongKonger

For me it's just that DL serves my needs best. I mostly fly TPAC from HKG and usually have multi-city itineraries with several domestic stops. I have had enough bad experiences with airlines supposedly in the same "alliance" not actually providing customer service/assistance to one another's passengers that I prefer an airline with a route network both TPAC and within the US. That leaves me with UACO and DL. UACO is a mess due to the merger and I wasn't a big fan of United even before the current mess. So DL it is.

In theory CX and AA would work. But aside from my aforementioned dislike of multi-carrier itineraries, CX is usually a lot more expensive and AFAIK provides no easy way to upgrade cabins such as the SWU. (I'd be happy to be informed otherwise.)

I usually buy M fares and upgrade to J with SWUs or miles. I assume this makes me a profitable passenger for DL, but I have no data to back up this assumption. If under whatever new system is implemented, I do not reach a medallion tier where I can get SWUs, I will probably just start buying the cheapest fares I can find, and not even necessarily on DL. I am sure DL doesn't care about one customer's plans, but hopefully they are taking scenarios like this into account.