Running an email forwarding service has to be a pretty thankless task, so hats off to the author if they're doing it right, even if the UI isn't quite on their

Running an email forwarding service has to be a pretty thankless task, so hats off to the author if they're doing it right, even if the UI isn't quite on their side. I send a lot of (wanted) mail and some subscribers have various forwarders set up which result in the eventual recipient server rejecting the mail due to the forwarded mail failing SPF and DMARC. It's a nightmare as we get the bounce backs telling us off but it's because the forwarders aren't, of course, sending from IPs included in our SPF record. (There are clearly ways to do it properly, but a lot of mail forwarding systems appear not to?)