Adding DoNotCreateDefaultSubobject to a class after placing an instance of that class in the viewport will fail to be recognized when duplicating the placed instance. This is not a hot reload issue, behavior also occurs if the editor is closed when compiling.
No- Behavior also occurs in 4.14.3 binary (CL 3249277)
Duplicated copy still have arrow component showing
Duplicated instance follows code rule of not creating default components when set
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-43019 in the post.