Sounds like she is developing a very strong feeding response. Mine would do the same thing, mostly for my own mistakes. I don't feed her in a separate cage. I don't take her out as much as I should and finally, she always had a very aggressive feeding response (she rips the frozen thawed rats right out of the tongs, often before i can open them up to release the rat. Now I just hang on tight so she doesn't pull the tongs out of my hand too LOL).
However, when I want to take her out of the cage to either clean or handle, I bring her cage down off the shelf (I have to inorder to get the cage open) and just let it sit on the ground for 20 minutes. She comes out of her hide and will strike any shadows coming near the cage, or wait right at the top of the cage where the door is, watching. I wait till she calms down and goes back to exploring the cage, or into her hide. Then when I open the cage if she doesn't smell rat, she typically stays calm. I can take her out and put her into a holding cage so I can clean, or just hold her for awhile.
My female bit me when she was around 18 months old, and it hurt then, so I definitely don't recommend letting her bite you. I have used gloves with my female time to time, till I figured out the above method.
I switched my female onto rats .... actually I don't think I fed her anything other than rats for as long as I owned her (and I bought her as a hatchling). An 18 month old BRB should have no troubles with weaned rats. My 3 year old (well three and a half now) female is eating medium to large rats easily. Heck she probably eat two if I gave them to her, but I don't want her to get too fat either, I want her a nice healthy weight when I breed her next season (she could go this season, but I didn't want to have too many baby snakes on my first season breeding snakes in general (have a ball python and corn snake breeding this year).
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PHLdyPayne