This is crazy, it sounds like they are doing this on a relatively large number of flights, and on a regular bases as well.
Just to the way p*** off their customers paying for C and then finding out they could have saved $$$$, got the same hard product, without the service.
It’s one thing doing this every once in a while, but that isn't the case here.


By the way, personally, I haven’t stepped foot on an LY aircraft for a while now, but in the days that I did, I came across this a number of times, and even as a Gold was never allocated a seat in the C cabin.
It seemed totally random, and in fact on one flight (which I mentioned here once before) it was a 767 from STN which was occupied mainly by charter passengers, I asked the purser whether I could get a proper glass for my wine from Business class only to be told by him that there was no Business class operating on this flight...
Imagine how annoyed I was when I went up to see the Business class cabin full of people and kids that with all due respect looked like they had never travelled in their lives, while I paid a full Y fare on that flight (booked fairly last minute) and was stuck in the back.

Funnily enough, the only time I remember being sat in C being operated as Y, was on a flight from LCA on a 747 many years ago where a friend and I were allocated Upper deck seats for the 40 minute flight, and I had no status with LY in those days.