I just stated my new site and have no real content on it, but my first sign up and a couple of others has this .pl extension on their email. I investigated the origins on Word fence plugin and found that one member with this email .pl was from china and the others was from Poland. All of them have been blocked totally from my site. I’m running a local services and have the option on Word-fence plugin to block out a country with one click, cool option against the war on spammers.
Thank for the links “notaweedpecker” I learned something that was needed to be known by anyone who deals with domain names like myself.