The A400 owner with the top binding matching the top material may have been misled by the early (March/April 1931) photos of the A400 during development. See the May 1975 Newsletter in "Phil Allin's Newletter" in the Resource section. There are many such features not found on production A400s when the body type was released in May 1931. On the other hand, most of the surviving cars probably do not have the original top fabric today.
Phil Allin