I also have the issue of thumb ratings and song seeds disappearing. I had a monster station with more than 40 seeds and over 600 tracks thumbs-upped. I built it up while I was in college 5-10 years ago, and started listening to Pandora again after getting an Amazon Echo 2 years ago. I play it probably once a week or so, and have continued to thumbs up tracks when I hear one I like. I just was listening to it on my phone today and went to go look at my thumbs up list to see if there were any songs on there I'd like to buy, and now there are exactly 100 songs on the thumbs-up list, and some of the seed tracks are missing too, while other seed tracks are in the list twice! Is that even supposed to be possible? I mean, same artist, same album, too.