A bit more digging and the product photos on Bilstein's online store show Eibach labels on the springs in the B12 kit. So I've got to assume these are the exact same kits just branded differently?
https://web1.carparts-cat.com/defau...BBC86664ACB81238D289483AD7D018004&14=4&12=130
https://web1.carparts-cat.com/defau...BBC86664ACB81238D289483AD7D018004&14=4&12=130