Hello,
It seems you’re looking for a way to display the subscriber’s registration date in a newsletter or email campaign using a tag similar to {registration_date}. While this specific tag is not mentioned in the standard list of tags provided by most newsletter services, it’s possible that the feature you’re requesting could be implemented by the service provider if it’s not already available.
For now, you might want to check the documentation of your newsletter service or reach out to their support team to inquire about the availability of such a feature. They might offer a workaround or even consider adding it in a future update if it’s a feature that other users could benefit from as well.