Now, when an email arrives from unknown sender I get option to delete/block or allow, this is OK. I use it and it will block them. But what happens with these spam is that the email address after the @ which it uses to block any more coming in changes. You can see most of that part is the same but they keep using a different few letters as like a prefix after the @.
Can it be set to block emails with a certain string in the part after the @ and not go on the whole thing?