I have a folder/album structure in Photos.  The folders are years, and the albums are inside these folders for months and events during the month.  When moving photos around between albums, I’m not seeing them moved.  They are copied and I have the same photos in the source and target albums after I drag them to the target folder.  I have to go back to the source album and re-select these and from the context menu select remove from album.  When these photos are in the source and target albums.  Is there just one original photo and the other is a reference to the original or do I have two actual photos?  One being the original and the other a duplicate?  I just want to ‘move’ them between albums.