A substantial number of unaligned mails for some of our domains are reported under Forwarders-Vipre-*.electric.net. These mails have no DKIM signature, and SPF Domain is typically bounceXXX .electric .net.
Examining DMARC failure reports, these mails appear to be autoreplies and NDRs, i.e. mails with no RFC5321.From/envelope-from/return-path headers, so the receiver is using the delivering server’s HELO/EHLO as the SPF Domain which does not align with the RFC5322.From address (firstname.lastname@example.org for autoreplies or email@example.com for NDRs).
Has anyone else noticed something similar?
How can we improve deliverability of these mails?