Reparenting of blueprint function library to C++ class

I have a BPF i created in blueprint, inheriting from the Blueprint Function Library class.
Now i made a C++ class inheriting from the Blueprint Function Library class, and wanted to reparent the blueprint to inherit from my C++ class. But i can’t because the parent class in the BP’s class settings is greyed out and there’s no “Reparent” option in the File menu if i have my BPF open.
I know that BPFs can’t inherit from other blueprints, but they can from a C++ class. My C++ class is Blueprintable, so I’m not sure why i can’t reparent the BPF.

I am having the exact same problem… has anyone found a solution for this?