Which user(s) can activate erased Mac with their device password after Mark As Lost?

[yurkennis]

I have the following 3 users on my M1 Macbook Air 2020:

• userA: admin created during macOS installation, no AppleID connected
• userB: non-admin, its own AppleID connected, FindMy disabled
• userC: non-admin, its own AppleID connected, FindMy enabled

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After I invoke Mark As Lost in FindMy iPhone app logged in with UserB's AppleID and rebooting into Activate Mac, I can Erase Mac without providing any user credentials. After Mac is erased, I need to activate it:

• either by providing AppleID and password
• OR via Use Device Password option

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Now the question is: Which of UserA, UserB, UserC device passwords should be accepted for "Use Device Password"?

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My own experiments gave inconsistent results:

• after Mac was locked when UserC logged in, I managed to activate it with UserC's device password
• after Mac was locked when UserB logged in, I failed to activate it with any of UserA, UserB, UserC device passwords: error messages varied between:
  • Activation lock server cannot be reached
  • The password for this Mac can no longer be used to remove Activation Lock. The password was entered incorrectly too many times

Each experiment takes a couple of hours, so I hope there's official docs / third-party research on the topic.

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Some further details of my setup:

UserC's AppleID is an adult, non-guardian member of family owned by UserB.

FileVault enabled during initial MacOS setup; encryption key not associated with any AppleID. Password reset using AppleID is disabled for all users.