I sold my gen 5712 couple years ago, so I can't have a look, but I was always under the impression, that the different engravings were actually tells that the movement did come from another watch (the 240 was used all over the place), but that the 5712 had 1 version of the plates. If there are in fact different iterations (and it would not surprise me with Patek, but it would surprise me with the 5712 specifically), then ignore my comment.
Now I have to look into the font variations on the 5712 movement plates. Fuck My OCD