SMTP settings for Custom Email Domain in iCloud+ beta?

I'm currently testing the new custom email domain feature in the iCloud+ beta. I was hoping to get some use out of this for server applications, but I need to figure out the SMTP settings in order to send emails using custom applications.

I've followed the steps in HT202304. However this doesn't seem to yield the expected results when using a custom domain address. Do the instructions in this article work for custom domains or is there a different solution?

That is a good point. So far I've had issues with third part apps and logging in when using custom domains. They don't seem to like using the custom email address as the username and have no functionality to accept an custom alias.

So far I've only used iOS Mail and the beta.icloud.com website to send email which works well.

I just sent an email from my MacBook using the new alias and checked my network, the request was sent to p60-smtp.mail.me.com. That is just a CNAME for smtp.mail.me.com so the standard SMTP server.

SMTP settings for Custom Email Domain in iCloud+ beta?
 
 
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