Email Aliases Not Functioning Properly in iOS 14 [Update: Possibly Fixed in iOS 14.2 Beta 2]
Affected customers have set up aliases in the Mail app for subscriptions, account signups, and more, as aliases are useful for concealing a primary email address and limiting unwanted messages. Those aliases are not working as intended as of the iOS 14 update, with the Mail app on iPhone and iPad ignoring the preferred alias that's selected when sending an email.
There appears to be no way for affected users to successfully control which alias is selected, leading to emails sent from unwanted addresses. A member of the Apple Support Communities describes the problem:
I have an IMAP account (not gmail) with a few aliases. I have been using this for YEARS and it's always worked fine. Today, I sent my first email from iOS 14 and it changed my from address after I sent the email. Note, the correct address was selected in Mail - it was changed during sending. I then sent some mails from other aliases, and those were also all wrong - never the right address.
I then double checked on my iPad, and the same thing occurs. For now, I have just removed all aliases.
Many of the complaints are from iCloud users who are using aliases with Apple's iCloud mail service, including those who have an older @mac.com or @me.com alias available to use with their @iCloud.com email addresses. Apple's Mail app appears to default to the @iCloud.com email address instead of the properly selected @mac.com that some users prefer. From the MacRumors forums:
One of the few who still uses @mac.com for the email address. After the upgrade I am noticing that the from address defaults to @icloud.com even though the settings still points to @mac.com address. Not sure if anyone here is noticing that.
The problem also affects email aliases associated with non-iCloud accounts, including those set up with Gmail accounts, so there appears to be an issue with all email accounts that have an associated alias that causes the Mail app to pick a random "From" address.
There seems to be no fix or workaround at this time aside from disabling aliases, and as pointed out on the MacRumors forums, the problem continues to persist in the iOS 14.2 update that's in beta testing. We expect iOS 14.2 to be in beta for at least another few weeks (likely until the iPhone 12 models launch) so there's time for Apple to add additional bug fixes.
Update: Early reports suggest that the second iOS 14.2 beta provided to developers on September 29 fixes the email alias bug.