The Mystery of the Paragon Cover

I had always thought the cover to Paragon #4 (signed "Steranko and Black") was drawn by Bill Black based on an original drawing done by Steranko that had appeared in an ad for Paragon #4 (signed "Steranko"). However, after having discussed this with both Mr. Black and Mr. Steranko, they both told me that Steranko provided Black with a pencil drawing, that Black inked and that was on the cover of Paragon #4. Neither could remember how the ad art came to be.