Canon has several firmware updates for its Cinema lineup of cameras, including the EOS R5 C, EOS C70, EOS C300 Mark III, and EOS C500 Mark II. While these firmware updates are not significant, all cameras will benefit from Auto Focus improvements and more lens support.
Source: Canon Firmware Updates for the EOS R5 C, EOS C70, C500 Mark II, and C300 Mark III Announced | CineD