My org sends some 3000 high value (invoices/receipts/statements) per day on behalf of itself and some 10 broker customers. I cannot control email recipients and need ALL bounced emails to be returned to the From: address (these vary per broker) - so they can be actioned. In a nutshell I send from some 10 distinct domains to some 400 distinct destination domains and cannot afford to have emails go missing.
After a bounce occurs, SG adds the recipient to a bounce suppression list and any subsequent emails are then dropped/lost.
The app.sendgrid.com GUI allows me to configure an Allow list where I can enumerate destination domains to be excluded from the suppression process, however I have no control of the destination domains and this is an ever changing list. Not practical.
SendGrid recommended the use of the API, but have just confirmed that this is not a permanent setting but something that needs to be done on a message basis.
My message source is via a dedicated Postfix server via a simple SMTP connector. We are not using the API. I can modify the Postfix server if required.
The API/json payload recommended by SG is:
"mail_settings": { "bypass_list_management": { "enable": "boolean (optional)" } }
But I am really not sure on how to implement this if this is really required on a per message basis. Possibly using Postfix?
Has anyone else run into the issue? Any recommendation? It is disappointing to say the least that a key feature such as bounce protection cannot be turned off at a GUI level.
Any suggestions on how to solve my predicament?
I can now confirm that prepending:
X-SMTPAPI: { "filters": { "bypass_list_management": { "settings": { "enable": 1 } } } }
Works as expected and undeliverable messages are returned to sender. TY SG support.