Overriding a subobject's class in a native base class can lead to that component being null in derived Blueprints (FObjectInitializer::SetDefaultSubobjectClass)

Overriding a subobject's class in a native base class can lead to that component being null in derived Blueprints. 

General Summary

• Create a native base class "MyActor" with a default subobject
• Subclass MyActor and override the subobject's class via FObjectInitializer::SetDefaultSubobjectClass "MyDerivedActor"
• Create a Blueprint based on MyDerivedActor (BP_MyDerivedActor)- note that the subobject is valid
• Close the editor
• Change MyDerivedActor's subobject class once again to a different class via FObjectInitializer::SetDefaultSubobjectClass
• Launch editor - open BP_MyDerivedActor and note that the subobject is now null

Using Attached project

• Download and Unzip InitRepro and generate project files (built against 4.26.2 CL# 16092969) 
• launch the editor 
• Open BP_MyDerivedActor and note that the "PathFollowingComponent" subobject is valid. (For convenience you can press the PIE button to print out the subobject's class name)
• Close the editor
• Open MyDerivedActor.cpp
• Comment out the constructor that overrides the subobject class to UGridPathFollowingComponent and Uncomment the constructor that overrides the subobject's class to UMyPathFollowingComponent.
• Compile and launch editor
• Open BP_MyDerivedActor and note that the "PathFollowingComponent" subobject is null.