I'm just having the same problem, receiving someone else's mail for months from different senders! The personal content is without doubts NOT SPAM. And the frequency means those mails are replied from the other account! Obviously senders detect after a while they have the wrong email address if they wrongly use email....@gmail.com in spite of email....@hotnail.com because they will ask for answer. But this is not happening since I'm still receiving personal email from someone else's mail frequently, so it means someone is using email....@gmail.com for reading and repplying while I have the emaila...@gmail.com.
Does google introduce this feature after allowing different variations to be signed up: email.address & emailaddress?
Can someone confirm if they ever received an email thread with replies of the twin email? I didn’t!!!! But threads/chat can be managed in a different way.
There's a way to confirm: create a fake new blog, send a friendly email to the twin email telling him to see (our nude friend drunk in the office vomiting his boss desk) and track if someone curious enters the site!!! This will conclude our worst fears!