While it has never been explicitly explained why Leon made the decision to walk away from the character, it is believed it was in connection to his other work.
Leon doesn’t just work in front of the camera, but also as a director, having filmed a number of short films.
In fact, this is the reason most believe he left Vera, as the star was starting production on his first feature-length film, Orthodox.
This was actually a theatrical adaptation of his previous short film from 2012, sharing the same name.
source: express.co.uk