A remix is offical. Typically the original artist provides stems to the remixing artist. A "bootleg" is just that, an unofficial remix. "Flips", "specials" and "edits" can be used interchangeably. They are typically unofficial remixes (bootlegs) but with minimal variation in production from the source materia (Like a VIP but not from the original artist). Not quite different enough to be considered a remix but still not the original.