MacOS Big Sur 11 beta 10 installation fails with BAU

Download BAU (macOS Developer Beta Access Utility) and download the Mac installer for 1 hour after installation.

The download is successful.

However, when I click the downloaded installer, a pop-up is displayed stating that the file is damaged and cannot be installed, and the update cannot be performed.

Is there any way to solve this problem?

Or is there a way to install or update the ipsw file downloaded by DTK Mac mini alone?
(The restore method seems to require another Mac.)
MacOS Big Sur 11 beta 10 installation fails with BAU
 
 
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