Silicon DTK - macOS update

Update to Big Sur beta 4 fails on the DTK with the following error: The base build is not compatible for this install method
Any ideas?

Code Block
Failed to download & prepare update: Error Domain=SUMacControllerError Code=7722 "[SUMacControllerErrorPreflightPrerequisiteCheckFailed=7722] Failed to perform PreflightPrerequisite operation: com.apple.MobileSoftwareUpdate.preflight.error(Preflight):12 | The base build is not compatible for this install method.
-> Current device configuration requires an alternate installer to perform the update.: [com.apple.MobileSoftwareUpdate.preflight.error(Preflight):12|Unknown Error Indication|]" UserInfo={SUMacControllerErrorIndicationsSummary=|Unknown Error Indication|, SUMacControllerErrorIndicationsMask=8, SUMacControllerErrorIndicationsDescription=-> Current device configuration requires an alternate installer to perform the update., NSUnderlyingError=0x123e07aa0 {Error Domain=com.apple.MobileSoftwareUpdate.preflight.error Code=12 "The base build is not compatible for this install method." UserInfo={NSLocalizedDescription=The base build is not compatible for this install method., NSLocalizedFailureReason=The base build is not compatible for this install method., MSUPreflightAlternateInstallerRecommended=true}}, NSDebugDescription=[SUMacControllerErrorPreflightPrerequisiteCheckFailed=7722] Failed to perform PreflightPrerequisite operation: com.apple.MobileSoftwareUpdate.preflight.error(Preflight):12 | The base build is not compatible for this install method.
-> Current device configuration requires an alternate installer to perform the update.: [com.apple.MobileSoftwareUpdate.preflight.error(Preflight):12|Unknown Error Indication|], NSLocalizedDescription=Current device configuration and target is invalid for install in the current state. Please try again.}


Update: DTK successfully backed-up and then upgraded via the App Store to macOS 11.0.1. I suppose the other problems here were related to unreliable betas.
Silicon DTK - macOS update
 
 
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