Although the end of the film hints at possibly exploring some Amityville territory, a scooper over at AICN is saying otherwise...
Because of the hints dropped towards the end of the film some fans have thought the next Conjuring (and we know there’s going to be one… the movie’s made over $100 million now) will center around the Amityville case, but if this report is accurate then that’s not the case at all.Source: Ain't It Cool News
The case file they’re looking at occures in the late '70s and centers on two sisters in Enfield, England, who were allegedly possessed. Warren said she personally saw them levitate and even saw one of the sister dematerialize in front of her only to be found 20 minutes later stuffed into an oversized fuse box, contorted in such an unnatural way that they couldn't have replicated it if they tried. She also said that the demon spoke directly to her husband on many occasions. Warren cited this case as one of the most terrifying experiences of her career.