Currently Version notifications are generated when the Version entity is created, which happens as soon as a movie is uploaded. But uploaded movies have to be transcoded before they can be streamed for playback through the web-based Shotgun Review tools. So with the current notification system, you know when a movie is uploaded as a Version and begins to transcode, but you are not notified when the transcoding is complete and the uploaded Version is playable. You should be able to turn this option on or off via following settings for each user.
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