Wedge-shaped night side (shadow bug)

[Xriqxa]

So I placed two binary Proxima Centauri's near Mars' is orbit in the solar system simulation, and Earth adopted a pretty messed up orbit. Apparently, it's night side wants to participate in the whole "messed-up" business:

[Jim Jam Science Mans]

Where are the stars in comparison to the Earth? It could simply be that it's at the right time of year to be receiving more light than dark due to the presence of stars inwards and outwards of its orbit.

EDIT:
I made a quick and dirty similar situation and the wedge changes based on time of year and relative orbital position. Does yours?