A "proper" release is issued when the initial upload contains one of the following issues:
If you see in a file name, it is almost always the best version to download , as it solves a known problem found in the "Internal" or original release. [Witanime.com] SMNB EP 12 END BD-HD.mp4
The sound doesn't match the characters' lip movements. A "proper" release is issued when the initial
The site or group that encoded/uploaded the file. [Witanime.com] SMNB EP 12 END BD-HD.mp4