@StoobyDoo I am afraid it is not possible. I don't think we can set up a timer so that the self-created accounts will be deleted automatically once the timer expires. Unfortunately, an API call is not available to delete users either. Please leverage the "Make a wish" button on the dashboard to request this feature. Hopefully, we can come up with something like this in the future.
That best bet, for now, would be to delete them from the user's page from time to time.
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