During the GoPro Q4 2016 earnings call, the company's CEO Nick Woodman confirmed that a new Hero 6 camera will be announced later this year:
“Yes, we can confirm there will be new cameras and other accessories released during the year and new camera namely being HERO6. But we’re not going to share any information as to the timing or any other details around the release of those new products as you can imagine.”
Via Ubergizmo