After the announcement of Sony a7R IV(B&H Photo Video/Adorama/Amazon), Sony currently still have 3 unannounced camera codes registered. One of these unannounced camera should be upcoming a9 II. The official announcement is expected in late 2019.
Currently, a new full frame CMOS sensor IMX554 is leaked on the web, the specs of IMX554DQC is an ultra-high speed 30MP BSI and stacked FF sensor, and up to 60 fps at 30MP. As upcoming Sony a9 II is a sports/wildlife camera for Tokyo 2020, this make sense it could use this IMX554 sensor. Stay tuned for more info.
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