I have a hen who is fine everywhere, EXCEPT when she's in a nest box. Not broody, just laying an egg. She pecks HARD, and I'm not pleased, but haven't fixed that one!
If anyone leaves, she's on the list to go, but I'd hate to send her to another flock without full disclosure. She might land...
I don't expect to be pecked, or jumped on, ever. Watch flock members interact with each other. The birds higher in the social order aren't pecked or harassed!
I'm not a chickens, and not part of their pecking order, and don't expect to have any bird try to 'manage' me.
Use enough force to be...
She is being rude, not necessarily actually aggressive, but do stop this behavior.
Don't actually hand feed goodies, if you have been. Toss stuff on the ground instead, while calling them to you.
Have them respect your space, and react immediately if she doesn't move out of your way. Bump...