Re-parenting blueprint actors do not lose interfaces associated with their previous parent blueprint

Re-parenting blueprint actors do not lose interfaces associated with their previous parent blueprint. Interfaces and interface functions can no longer be deleted from the re-parented actor.

1. Download and open attached .zip file
2. Open BP_A
3. Open Class Settings
4. Reparent blueprint to "Actor"

Results:

Interface and Interface functions remain in blueprint after re-parenting. These cannot be removed.

Expected:

After reparenting and/or compiling blueprint, the interface and interface functions are removed from the blueprint.

Changing parent class which implements the same BP_Interface creates ghost functions !