You are correct that for the first production year of the P38 there was parallel production of the original shape. These had a decal "Classic" on the tailgate. Therefore the official model title "Range Rover Classic" (RRC), however while the others had the "classic shape" they were not the RRC model and IMHO are "Range Rover classic" (RRc) an important distinction for a pedant like me.
My RRc is a Phase II Hi-Line called "Vague"! ;)

