Description: The "Delivra Opt-In" check box seen in Salesforce only determines whether or not a contact is being synced with the Delivra integration, it will not indicate a status change of that contact in Delivra. If it's unchecked in Salesforce, that record will no longer be part of the data sync, it does not mean unsubscribe. Any contact you wish to unsubscribe must be done in the Delivra account.
Additionally, the Salesforce data sync cannot override a Delivra contact's status back to normal. Once a contact is held or unsubscribed in Delivra, the data sync will not update that record.