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Due to an internal improvement of how client credentials access for the on Demand API is set up, all access tokens still valid during deplyoment deployment are invalidated once and cannot be used any longer.
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For each set of on Demand API credentials (client_credentials access) a technical administrator profile is created automatically.
The change allows improved security because the corresponding application authorizations can be defined more precisely.
IMPORTANT: Do not change nor touch the admin user details nor roles which are created automatically.