RE: iCloud/Apple Mail contact.

Did you ever manage to find out who at Apple to speak to about getting things added to or changed in this database?

Quite irritating how there is zero public-facing information about this. Also, an Apple employee authored RFC 6186, yet they don’t implement it??

– Nathan

There is public-facing information: Prepare Your Network or Web Server for iCloud Private Relay - Support - Apple Developer

Which includes ranges to allowlist, should providers choose to do so: