It's not Spotify pulling the music but the rights holders. Spotify cannot list music unless they have a license to do so and some publishers are still stuck in the past and scared of the internet. Some others will put up new albums for a short period and then pull them in the hope that you'll go out and buy them (!)
Complain to the publishers.
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Listening on Windows, Android and Sonos. Tweeting it at @davelicence