The Snapdragon 618 and 620 will henceforth be known as the Snapdragon 650 and 652, respectively, in order to separate them further from the existing and less powerful 615, 616, and 617 lineup.
http://www.notebookcheck.net/Qualcomm-moving-Snapdragon-618-and-620-to-the-new-650-series.156296.0.html