After Sony officially announced a7 III (B&H/Adorama/Amazon), next cameras from Sony will most likely be Sony a7S III and Sony a6700. The announcement for Sony a7S III could be around Photokina 2018 in September, and announcement for Sony a6700 maybe in the second half of 2018. Stay tuned for more info.
Here are two specs predictions video of Sony a7S III (Above) and Sony a6700 (Below) by Jason Vong.