As far as I understand you would like to display the DateCreated field in the Subscribers grid in the backend under Marketing -> Subscribers.
Unfortunately this process does not expose the DateCreated field and since this filed is not returned from the service it is not possible to display it in the grid.
Currently there is no possibility to extend the SubscriberService in order to achieve the desired functionality, as it would require replacing the whole service, since the SubscriberViewModel type is used in all its methods.
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