My 1100 gram girl I just got ate for me once. Then refused this last feeding.
If your husbandry is spot on. Just keep prescenting and trying. Even though you may have everything just right. The older snakes can sense the atmospheric pressure differences of the winter/breeding time.

That's what I read somewhere.

I guess there's no real time frame for them to be off feed. They'll just eat when they're ready. Which is a scary thought.

Just keep trying. That's what I'm doing. Good luck to you!