Forwarding emails - false SPF records cause classification as SPAM
Email messages accidentally sent to internal cpm addresses (e.g. firstname.lastname@example.org) instead of the usual "real world" addresses (e.g. email@example.com) are forwarded to the correct email address by pm. servers.
The sender of this forwarded message used to be the original sender, but due to email spoofing concerns we now changed this concept. Instead of forwarding it by acting as if we are the original sender, we now send it on behalf of the original sender, which is the formally correct way.