After Sony Alpha a9 (Amazon/B&H Photo/Adorama) officially announced, next high-end full frame mirrorless camera will probably a high megapixel camera, and the name will be Sony a7R III or a9R. According to recently rumors on SAR, a7R III or a9R will have a 60-70 MP full frame sensor, the announcement of this camera will be after 3-4 months from now, that means we may see Sony a7R III or a9 later this year.
After Sony released the Sony Alpha a9 (Amazon/B&H Photo/Adorama) full frame mirrorless camera, the next full frame mirrorless camera from Sony will most likely be Sony Alpha a7III. Previous rumors said that Sony will announce Sony Alpha a7 III in June, now according to source from SAR, Sony has delayed the launch of Sony a7 III to November, 2017. This means Sony a7 III announcement could be around September or October, 2017.