Library (+) vs Favourites (Heart)

[Andy_whatever]

Plan: Premium

Device: Samsung Galaxy Note 4

Operating System: Android 6.0.1

My Question or Issue

I used to use extensively the automatic Favourite Songs Playlist in Freemium to define my Music Collection. After changing to Premium it gets very confusing. Some songs are in my library and have the heart, some are only in my library but miss the heart and some have a heart but are not in my library? How is that supposed to not confuse anyone? Why Freemium and Premium can't just be the same UI with some restrictions? I regret to have changed to Premium because of that.

My main question now is what will define my Favourite Songs Playlist when my Premium test period runs out and falls back to Freemium? Will it be the library or the favourite songs or both?

A related question regarding maintenance: Where can I see the Favourite Songs Playlist (all songs with heart) INDEPENDENTLY wether they are in the library or not and how many songs are in this playlist already in Premium?