AMD Catalina Hackintosh Upgrade to Big Sur Problem - Help with error?

I'm trying to upgrade my working open core Catalina install to Big Sur and on reboot I get this error.

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https://preview.redd.it/x7zfxfeixhz51.jpg?width=1536&format=pjpg&auto=webp&s=4fa6751895d0f207203d80c5da5691e911e9725a

Any ideas?

Thanks in advance