We would like to use a different custom Return-Path for each domain that we send marketing emails from.
We have paid for a dedicated IP address so we can use a custom Return-Path for our marketing emails. However, this custom Return-Path can only be set for one of our domains. We have set it on our primary domain, but we would like to set different custom Return-Paths for our secondary domains. Other email providers (like Amazon SES) allow us to set a different custom Return-Path for each email domain we use.