http://www.sonyrumors.co/new-a7-series-or-a9-sony-registered-a-new-camera-ww158299-in-china-miit/
Sony has just registered a new camera with code name “WW158299” at China Gov website MIIT. The code name “WW158299” is liked a new mirrorless camera according to previous cameras: WW213019 is a6500, WW067022 is a99 II, WW605351 is RX100 V.
According to previous rumors, Sony is planing to announce new a7 series cameras: a7 III, a7R III, a7S III and new flagship mirrorless camera Sony Alpha a9 in 2017. So this unpublished model could be any of these cameras, or a new A-mount camera.