When Dolphy puts in his Author Notes that someone is writing a #B story it means that the story to other person is writing is running parallel to Dolphy's story
Ex.
Dolphy Blue Drake-Author-The Conversion Bureau The Earth Gate Saga-Book 2 A---> this is the cannon timeline that the story follows a.k.a God in writing format
Username- Secondary Author-The Conversion Bureau The Earth Gate Saga-Book 2 B--> This story is running parallel to ^ story i.e it is on a railroad track with Dolphy Blue Drake's story Book 2A