Since yesterday morning, iCloud mail connectivity has been iffy or entirely absent for some subscribers, and Apple's not commenting aside from the "we're working on it" notice.
It seems the non-US users are the one who are most affected.
source
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As for me, iCloud.com is...
Yes!
That's correct.
Apple is rolling out to all its me.com or mac.com customers new email address with the iCloud.com domain name.
This is a FREE upgrade to all APPLE ID holders.
Official Link
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