After completing the download and about 10 minutes in the prepare stage, the installer fails saying something went wrong with the download. (Which means it unnecessarily restarts the download when I try again, but okay.)
From the system console I got this which looks like a hint:
[UpdateAttemptFailed] SUCoreUpdate update attempt failed with error: Error Domain=MobileSoftwareUpdateErrorDomain Code=44 "bridgeOS personalization failed" UserInfo={target_update=20C69, NSLocalizedDescription=bridgeOS personalization failed, NSUnderlyingError=0x7fc127df7630 {Error Domain=OSPErrorDomain Code=201 "An error occurred during personalization." UserInfo={NSLocalizedDescription=An error occurred during personalization., NSUnderlyingError=0x7fc127d14080 {Error Domain=AuthInstallErrorDomain Code=11 "(null)"}}}}
I hope you're not breaking your own firmware here.
My device: 2019 MBP 16", 2.6 GHz 6-core i7 with Radeon 5300M. Running Big Sur 11.0.1.
marcelsamyn
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