Your observation is a figment of your imagination, or perhaps something misconstrued. There is no difference in what 77W planes fly where around the world except for aircraft type (77H vs. 77G). 77G destinations in North America (YVR, SFO, LAX, YYZ, EWR) have the same 20 birds cycle through as 77G destinations in Europe (AMS, MAD, LHR, CDG, MAN, FCO) and Australia (SYD, soon to be MEL too). Same situation with 77H: destinations in North America with this plane (YVR, SFO, LAX, ORD, BOS, JFK) have all the same 33 birds cycling through as the 77H destinations in Europe (LHR, CDG, FRA, MXP, ZRH).

The only difference is between 77G and 77H, which are different layouts as you know. (And of course, 35G flies to DUS and LGW now, and soon will fly to some more European destinations).

Now, there are indeed subtle differences. It's true, the oldest 77Ws are all 77H birds. This includes B-KPA through B-KPX, which is the last 77H before 77Gs started getting added to the mix (B-KPY through B-KQZ are a mix of 77G and 77H, and B-HNL...CX's 53rd and final 77W, and sole "out of sequence" 77W is also 77G).

I don't fly economy on these planes too often, but the notable difference in J class is the early sequence 77H birds (I think through B-KPX, but this might be off slightly) do not have the ridge on the back of the window-side J class "countertop" thing next to the window. This means it's easy for your stuff to fall into the seat behind you. The 77G birds and all 77H birds starting with B-KQ.. have a little ridge to protect your stuff.

Many of the early-build 77H birds were previously "77D", which was a no-longer-in-existence 77W config. In this config, J class is identical...the material changes are in PEY and Y. I *think* some (all) of the original 77D converts are these ones without the "ridge" I describe above, and haven't had their seats replaced. Thus they have slightly older Cirrus J seats, maybe AVOD/screen is scratched? I don't know but some are older some are younger. 77D was active between 2011-2013, before quickly being canned when PEY was rolled out.

Long story short, yes some 77Ws are older than others, and in the "oldest" J class on 77H (formerly 77D) birds you're likely to have ~4-5 year old seats. But there shouldn't be too much difference at all, meanwhile newer-sequence 77Ws fly to all the destinations....they don't discriminate against Europe. Just like older-build 77Ws visit North America. In fact, since North America gets far more 77H flights than Europe, you could say on average the age of the 77Ws flying to N.A. is definitely older than the ones flying to Europe. Although this doesn't really mean anything except for trivia!

You can get more details here CX / KA Fleet, Configuration and Route Details

Correct!