Kingsnake off food

[Moreau]

I have an adult female Grey Band, and she has been off food for the past couple of months. She is strictly using the cold hide, and is not venturing under the heat at all (RHP). Is she trying to brumate on her own? Should I just stop offering food at all? How long do they usually "winter" for? She has just been refusing all food. She has been less active as well. She has not lost any weight that I can see.
She is my only kingsnake I have ever had, so it is a new thing for me. My first colubrid really.


EDIT: So sorry about the double post, I lost network access for a second and didn't realise it posted twice.