Apple Music has duplicated my entire library

I have looked around and seen this has sort of happened to some other people but I couldn't find a decent answer or reason: Last year I finally converted from iTunes to Apple Music (subscription), bringing a large amount of my own music across. Today I opened Apple Music and it has duplicated every single song from my hard-drive - it hasn't downloaded them, just saved them. What is weird though is all the song's information has come with it - even duplicating the plays, date added, etc. I can bulk delete the duplicates by showing duplicates and sorting by cloud status (the only difference between the two versions of each song) but I wanted to ask thoughts here before I do anything irrevocable...