Mark previously seen episodes/movies at custom date/time
There is no way to mark an episode or movie as seen at a previous time if I couldn't check into at the time.
The «seen» date of the button «mark as seen» exposes a wrong date since the media could have been seen even before that time.
This is now possible from any movie or episode page. Click the right icon in the watched button and you can specify the time you watched it.