yes I’ve had tracks on playlist become “Not available”. This is caused by the upgrades and patches they deploy. Not a major issue as you can reload the track into your playlist but it’s annoying I agree.
I had not verified this claim until recently, when I discovered that I had lost Jean Pierre by Marcus Miller from my playlist. To my astonishment, I found that the entire Marcus album had disappeared, along with several of his other albums such as Free, Renaissance, and others. I have had similar experiences before, where albums or songs gradually vanished from Qobuz library over time.

