Managing subscribers closely is important when members of your audience change role or email address. We have updated the filters and status for contacts in both the newsletter subscriber list and the contacts page.
You can now identify contacts who are subscribed, not yet subscribed, unsubscribed, those who bounced and marked you as spam. Hopefully you don't have any in this last category as it reduces email domain deliverability. Remember to keep a clean list of subscribers who are happy to receive your emails! See subscriber guide.