While listening only to one station, which has thousands of thumbs up and down, I have recently noticed tracks play which I have given a thumbs up in the past but show no thumbs up now. The songs are all from Pandora's library, I have not uploaded any material. I also recently paid to upgrade again to Pandora Plus, it had expired for some days. Not sure if the disappearing started when the paid subscription expired.
I have read the other posts on disappearing thumbs up and don't believe the feature descriptions about shuffling between stations applies to my use case.
Station: Peter's big messy station
Example track with disappearing thumbs up: Helpless by Sugar from album Copper Blue
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