Capture One 8.3.1 now supports the new Sony cameras. Download at phaseone.com/en/Imaging-Software/Capture-One.aspx. Release notes here (pdf file).
A7rII and RX camera preorder list:
In USA:
A7rII at Amazon, BHphoto, Adorama, SonyStore US, FocusCamera, Uniquephoto.
RX10m2 at Amazon, BHphoto, Adorama, FocusCamera, Uniquephoto.
RX100m4 at Amazon, BHphoto, Adorama, FocusCamera, Uniquephoto.
In Europe at:
A7rII at Sony DE, UK, FR, IT, ES, NL, BE, CH, AT, SE, FI, NO, PT. Wex UK.
RX100m4 at DE, UK, FR, IT, ES, NL, BE, CH, AT, SE, FI, NO, PT. Wex UK.
RX10m2 at DE, UK, FR, IT, ES, NL, BE, CH, AT, SE, FI, NO, PT. Wex UK.
In Asia at:
A7rII at Digitalrev, CameraPro.
RX10m2 at Digitalrev, CameraPro.
RX100m4 at Digitalrev, CameraPro.