This is now live!
We’ve released the ability to update opt status per subscription type via workflows; the new action is called ‘manage subscription status’ and can be founder under the ‘Contact Properties’ section of the Workflow actions. For GDPR-enabled portals you can opt a contact in or out and set a legal basis for communication. For non-GDPR-enabled portals it simple either opts contacts in or out.
Opted out contacts will not be able to be opted in as only the contact can manage their preferences and the opted out status won’t be overidden.