I was just able to setup me@ so looks like they sorted it out 
This darn hop errorApple obviously changed something - all family members are pre-filled in the domain setup, and for wife and son already confirmed. And they receive in their iCloud mailboxes
I, myself, still end up in hop error
Will need to try this afternoon.just checked - in my family members beta.icloud pages, they can finally access the domain settings without error
Epic! I can confirm I’ve created my wife’s email and she is a family member!! Finally this works 😜💪🏽🤛🏽just checked - in my family members beta.icloud pages, they can finally access the domain settings without error
Yes yes yesssss finally everything is perfect 👍🥳just checked - in my family members beta.icloud pages, they can finally access the domain settings without error
Now resolved, was able to add wife’s email address and it’s working on her devices.Also experiencing the same error when trying to add my wife’s email address at beta.icloud.com.
I've been thinking about this. The bounce error message is really weird because it is coming from mx01.mail.icloud.com.Apple obviously changed something - all family members are pre-filled in the domain setup, and for wife and son already confirmed. And they receive & send in/from their iCloud mailboxes
I, myself, still end up in hop errors ... weird
I removed the existing domain and waited about 2 hours to try to add it back again but now I just get an error that says, "There was a problem adding this domain. Try again later."I've been thinking about this. The bounce error message is really weird because it is coming from mx01.mail.icloud.com.
<owner@[example].com>: host mx01.mail.icloud.com[17.56.9.17] said: 554 5.4.0
Error: too many hops (in reply to end of DATA command)
That means the message is rejected after it is resolved to the iCloud mail servers? So it looks like it is a misconfiguration on Apple's servers.
It is supported starting today. One letter emails are X@ are also supported.Since using just initials for a custom email address - like ab@personaldomain.com - is also widely used, I really hope they also change the character limitation for custom email addresses pretty soon.
I removed the existing domain and waited about 2 hours to try to add it back again but now I just get an error that says, "There was a problem adding this domain. Try again later."
Checking with dig, all of the mail domain settings have been reverted to the registrars mail forwarding. Beta ¯\_(ツ)_/¯
I just tried a couple of more of my domains and they all report the same. So I think you are right. The domain setup is just down right now.Same here, just tried to test the process again.
"They're" working on it heavily at the moment I assume ...
Mine is coming from mx02I've been thinking about this. The bounce error message is really weird because it is coming from mx01.mail.icloud.com.
<owner@[example].com>: host mx01.mail.icloud.com[17.56.9.17] said: 554 5.4.0
Error: too many hops (in reply to end of DATA command)
That means the message is rejected after it is resolved to the iCloud mail servers? So it looks like it is a misconfiguration on Apple's servers.
Playing around now quiet some time with the e-mail domain apple is offering - I might have a silly question:
In simple words - what is the benefit letting apple forward these email addresses to my iCloud mailbox when I can define mail forwarding on the email address itself, giving the same results ? Better security ?
Hmm, ok the second has a point ... Thank YouFor me it's two things: removing unnecessary dependency on an email host/forwarder, and more importantly recipients of my emails seeing them sent from my domain, rather than an iCloud email address.