The subject of the email is asking you to upgrade to Imepria while the content of the email shows you your current tier.
I have been a classic, preferred and am now an Imepria customer. There's literally 0 difference. Same shitty RM. Nothing is better. It's just that you get a locker free(that too I've heard that many BMs deny by saying that they're running at full capacity and you have to start the 'email and call' game to make them cave in)