I thought CV3 was always set in 1476 to correspond with the "death" or the real Vlad III. It would make sense faux-historically, as in CV, it's his first "death" that triggers his cycle(or lack of) of resurrection.
Odd thing about someone bringing up 1472 as a possible date for Legends, would that make Sonia Trevor's OLDER sister then? If we can ignore the "first death" detail, big sis Sonia went off to fight Dracula, and four years later, little brother Trevor would do the same(perhaps because Sonia was raising her child).
Again, I'm not one for Legends, but I've ALWAYS made it known that I'd love to see a sibling dynamic in the CV series. Seeing something like a sister and brother having roles in vanquishing Dracula would be awesome.