When I delete a subscriber and then subscribe with the same email it is confirmed immediately indicating that something has been remembered about that user. My real interest at the moment is making sure the newsletter plugin behaves in a way I understand but it may also suggest GDPR issues.
Hi, it’s not clear your case. If you delete a subscriber all data about that subscriber is delete. If there is a new subscription with the same email address the usual subscription process should be started (with single or double opt in as configured).