a user (A) recently upgraded from iphone 4s to iphone6. A has 2 emails firstname.lastname@example.org and email@example.com..
firstname.lastname@example.org was the default email a/c he sent emails. his recipents will commend they can also see his email email@example.com . this also happens from the sms he sent out. not sure if this is some known settings to correct.
according to A, those recipents that commented seeing the email firstname.lastname@example.org are people who don't know about this 2nd email address he had.