It looks like they are going with 1964 for Season 4. This should be interesting because when you look in Vogue magazine from that year, the beginning of 1964 still looks very Jacqueline Kennedyish, with Chanel suits and pill box hats, but by the end of 1964 its more Twiggy with shift dresses, flat shoes and short hair. It will be interesting to see how they work that into the show.