okay, just to make sure I went back to folks at CX and confirmed. I wanted to make sure I was posting accurate info. Indeed what I wrote is correct, so don't really know what to say except that you've got your facts and/or experiences mixed up, or you made a false conclusion after a few experiences.

In fact, your Y26 ticket is quite low priority. There are 25 classes above that. I was told your Y26 priority would be roughly in line with a BC who started 3-4 years ago. You'd be trumped by someone with Y25 priority, who would be trumped by someone with Y24, etc.

Now, there are certain exceptions...like an "FOC", which is a annual 4-sector pass given to certain crew and it gives priority. I was told that if your FA friend with Y26 used an FOC she could be as high as Y11. So basically, you very likely can get a confirmed seat. There are other considerations that can one-off bump up your priority, like using an FOC back to a home-port if you're a recruit from another country. But again, FOC are limited quantity annually and most of the time the ID passenger is stuck with the priority they've got.

The whole point of what I wrote originally is that ID tix are not the holy grail many folks think they are, and some crew - especially newer, younger crew within CX - sometimes have to mill around or sit around without any clarity on whether or not they'll get on (or if they do make the flight, maybe they're stuck in a crew seat). All in, as someone with quite a bit of tangential experience, I would say lower-priority ID crew is not an enviable experience whatsoever, even if they fly on J class sometimes. If they can score premium seats, by all means I'm for them sitting there. Personally I couldn't deal with the stress of knowing whether or not I was going to get on the plane, and I can't even fathom what it'd be like stuck in a crew seat for a 13 hour flight from LHR.