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In the second case with a subdomain of your already validated main domain, you will still add department.example.org and *.departement.example.org with delegation to the department but you will not have to initiate DCV again, as the SCM is smart enough to know that example.org is already validationvalidated. As for your main domain, you should expect department.example.org to show as Validated at once, and *.department.example.org with some delay.
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