@Rookie{} , For the test "Making the localadmin user as a non admin by changing the integer value to 1, and then first tried with dynamic device group assigned, which failed and also the user group which also failed.", this is failed because "./Device/Vendor/MSFT/Accounts/Users/localadmin/LocalUserGroup" only support add operation. Changing is replace operation. So it will fail. we can see more details in the following link:
https://learn.microsoft.com/en-us/windows/client-management/mdm/accounts-csp
If we want to add the user into local administrators group, we can choose LocalUsersAndGroups CSP instead. Here is a link with more details for the reference:
https://learn.microsoft.com/en-us/windows/client-management/mdm/policy-csp-localusersandgroups
For the Autopilot admin and configuration profile to create local admin conflict issue, I will do test in my environment to see if I have the same issue. This needs some time. if there's any update, I will update here.
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