Once the communication email is changed, are there communications sent to the original email?
As far as forums profile is concerned. (link you posted) No, going forward all alerts go to new address once it is confirmed. You seem to be asking a microsoft account question which you can chat or email them here. (links at page bottom)
https://support.microsoft.com/en-us/help/12429
Regards, Dave Patrick ....
Microsoft Certified Professional
Microsoft MVP [Windows Server] Datacenter Management
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