When a constituent unsubscribes from an advanced mass email using the 'Remove my name from all future email correspondence' link eTapestry provides, their account in eTapestry is marked as Opted Out.
However, there are other ways of unsubscribing from an advanced mass email aside from using the standard link. For example, some constituents will use another link or feature within their email provider to flag the email as spam or junk. In these cases, the account in eTapestry is not marked as Opted out, since the standard link eTapestry provides was not used to opt out of future emails.
In those instances, the email address will still appear as Opted Out in a Delivery Report, despite not being marked as Opted Out on the eTapestry account. The reason for this is that eTapestry uses another provider to send advanced mass emails: Delivra. Whenever an advanced mass email is sent from eTapestry, eTapestry processes the request and passes it along to Delivra, who then puts the email into a queue and sends it from there. Delivra also tracks accounts that have opted out of emails that it sends, and when a constituent flags an email as spam or junk, but does not use the link eTapestry provides for opting out, Delivra updates that email address as opted out, while eTapestry does not.
The data within the Delivery Report is pulled directly from Delivra, and as mentioned an account that marks an email as spam or junk will be opted out within Delivra but not within eTapestry. In those cases, an email address will be shown as Opted Out in a Delivery Report within eTapestry (since the data is pulled from Delivra), but the account in eTapestry will not be opted out.