From my blog that I run with other members of HF and Baka called karma.moe: http://www.karma.moe/2016/12/blue-exorcist-kyoto-impure-king-arc-tv.html

The new "Blue Exorcist: Kyoto Impure King Arc" (also known as "Ao no Exorcist: Kyoto Fujouou-hen") show airing on January 6th (or 7th according to MAL) has a recently released Anime Visual. The anime is the next season to the original Blue Exorcist; it'll be an adaption of the Impure King arc, so it'll be a sequel. From talk in Reddit, it will just ignore the previous season's anime-original stuff and pretend we've been staying true to the manga the whole time.Talk says that they will have a "previously on Blue Exorcist" to clarify what happened and counts and what didn't.