I'm going to be flying a very very short (<500 miles) AA sector on 11MAR, which is going to qualify me as MPC Gold.

Later, on 16MAR I'm going to be flying CX transpacific.

I'm worried that my CX miles are going to post before my AA miles and this means that my long CX flight will be "wasted" for next year's qualification.

Should I worry about this?

Yes you should worry.

Technically here, you don't "qualify" until the miles hit...together with the record that AA has re: their miles posting for MPC (anywhere from 4-25+ days I've found, very inconsistent: I'm currently waiting for AA miles flown over a week ago to post, and distinctly recall one once the miles not hitting for more than 3 weeks, and also twice where they just never credited at all), there's a very good chance of your fear happening. As you know CX credits their miles pretty quickly, even from outports. Kinda a pain in the a$$ that they have this clause whereby it's when the miles post, and not when the miles are flown. Adds an unnecessary random element to the program in my opinion.

What you can do is this: You can wait and check your MPC account right before your transpac flight. If the AA miles haven't posted the few hours before your flight, you can remove your CX# from your CX transpac flight so the AA miles guaranteed credit first. Then, do a missing mileage request for the CX flight.

I think you should probably consider this, since you're going for GO...hence even if you're sure you can make GO next year, there's always the chance your travel patterns will change and then DM comes into the realm of possibilities. You certainly will be kicking yourself next year if you're at 113k because those AA miles posted late.....

If you decide to risk it, you always have the chance that CX will be kind next year if you just miss GO or DM and grant them to you anyway since you got caught in the randomness of the MPC mileage posting clause. It sounds like CX has given a number of people DM who didn't hit the threshold this year out of goodwill (aka, terrible economy), however, and I'm not sure if next year they'll be so generous this year given the economic rebound.

Why don't you give MPC a call and tell them the situation. They might give you GO immediately.

One alternative: If your AA miles have not hit by 15 March, remove your CX number from your reservation. The miles will not post. Save your Boarding pass and ticket until the AA miles do hit and then claim the missing miles via MP web site.

Usually I find that AA miles post in about a week. Sometimes less, sometimes a bit more. A bit too random to risk it, I think.

I might just remove my MPC number from the record if the miles have not posted.

There's no prospect of DM next year. This year I've been travelling more than usual and if I time everything correctly I'll be able to make my return trip ORD-LAX-HKG credit towards next year, so I'll only need about 52K more to requalify for GO next year, which might be doable.

The AA flight that will should qualify me for GO will be YYZ-ORD, only 434 miles, so one can see why I'm keen not to have my LAX-HKG flight post before that one!

Not wanting to fiddle around with unpredictable AA miles posting schedule, I've reorganised my travel schedule (with some creative routing) to get a couple of extra miles so now my qualifying flight will not be the short AA hop but my outbound transpacific sector on CX, so I know when the miles will post and will only "overqualify" by 115 miles, for sure.

Thanks for all your help.

As soon as you have done the 500 mile flight that qualifies you, call up MPO, explain your story and they should assist you. Make sure you keep your AA boarding pass in case they need a fax or email copy of it.

When is your CX MPC year end? If it's April or May then your miles are "wasted" regardless. Your concern only applies when your MPC year end is on or before March 15.

Otherwise I don't really see how your longhaul will be wasted.

Won't be wasted as OP's membership year will be reset when he moves from Silver to Gold.

Of course they will be wasted in the scenario the OP mentions. If he currently has 59,500 Club Miles, a 600 mile flight and a 8,000 mile flight then if the 600 mile flight posts first then everything's fine, the membership year is reset and the 8,000 mile flight posts as the first flight in the new year as a Gold. But if the 8,000 mile flight posts first, then in his new membership year as a Gold he will only have 600 miles.

The solution, as many people mentioned (before the OP rejigged his plans), is to simply delete the MPC number from the 8000 mile flight and claim missing miles later.

Thanks - I had specifically wanted to avoid this scenario because I prefer to have my MPC number on the record because I'm travelling Y and I tend to get upgraded a lot on long haul, probably on more than half my long haul flights. Don't want to lose out on that.

Instead, I'm flying an extra roundtrip HKG-BKK-HKG in Y to make up the 2K miles I need so I can qualify predictably based on 100% CX flights (which always post 2-3 working days after the flight), and all my AA flights will be in my new Gold membership year, so then I don't have to care about when the miles post.

OT: Although AA sucks as an airline in pretty much every way an airline can suck, it's great for earning Club Miles because pretty much any revenue fare will give you 100% Club Miles.

You know, usually it's the other way around, people tolerate AA because their FFP is a joke at giving away bonus miles, upgrade coupons, etc.

But you tolerate AA because you want to accumulate CX miles, which gives less bang per mile compare to AA... hmmmm....

I think you misunderstand me. I don't mean I'd choose AA over CX for flights because I get CX miles on more classes.

What I mean is that unlike other OW carriers, it's easy to earn CX miles on AA metal. For example, if I ever have to fly USA-UK, I would always choose AA instead of BA because I can buy a cheap fare on AA and still earn 100% miles whereas cheap fares on BA earn either 50% or no miles at all.