We’ve seen a few of these snakes and had mistakenly mis-identified them as a cat-eye snake (Leptodeira) at first.  The head pigmentation pattern is markedly different, which prompted us to consult Savage, but the pupil of the eyes are still cat-like, suggesting that they are nocturnal.  They are beautiful snakes and appear to be a bit less prone to musking when being handled… although it does bite.