It is a sedan changed into a convertible, in cases like that the class usually reflects the current state:
http://www.imcdb.org/search.php?resultsStyle=asList&sortBy=0&yearFrom=&yearTo=&makeMatch=- 2&make=&modelMatch=0&model=custom-made+convertible&modelInclExtra=on&origin=&madein=&madefor=&role=
(but not always :D)

The two others weren't (yet) missed. And last one does not contains any explict year info, how did you expect a change if none is asked?