This source is known to forward email
forwarding notes:Simplelists.com operates mailing lists products and services, and is aware of DMARC.
Simplelists.com is well aware of DMARC and may be able to help. Contact Simplelists support to configure.
Customers of Simplelists.com can white-label their lists to get DKIM into place.
Customers of Simplelists.com can white-label their lists to get SPF into place.