We have now had a response that the issue is resolved with the upstream vendor.
Any mail in the queue will deliver with a slight delay. Any failures will bounce back to the sender, which you can try re-sending.
Apologies for the inconvenience and we appreciate your patience.
We are awaiting spamrl.com to respond to the issue, which appears to be also impacting multiple email providers globally.
While we wait for a response, we are looking for work-arounds to the immediate issue.
Thank you for your patience while we work on resolving this matter.
We are aware of an issue impacting some clients relating to sending and receiving email.
You may receive a bounce back when sending email.
550 A URL in this email (domain . com) is listed on https://spamrl.com/. Please resolve and retry
Some inbound mail may also get sent to quarantine.
It appears an upstream spam service (https://spamrl.com/) may be experiencing issues and creating false positives. We have reached out to them for assistance and will update once we receive further information.