Offline mode playing songs I don't have downloaded

[asjenkins]

Something odd happened to me today with Spotify offfline mode.

I set Spotify to Offline mode so that I could take a walk and listen to songs I have set to download, however to my surprise it played a slew of songs that I do have saved but are not set to download. It even played songs from an album that I previously had saved but is no longer in my Albums or Songs library.

For what it's worth, I am a Premium user. Any idea on why this would have happened?