I got that email today too and in a couple of weeks I'll be starting my 6th year as a Unlimited cardholder!
I assume it's just a standard letter to every Unlimited member and it's just the wording that's confusing.
How is the wording confusing? If you've had your card for more than 12 months you will get issued the new one when it comes out. Simple in my mind.
Edit - Oh I get what you mean now. Yeah I would assume we will get it on day 1 and not in 12 months time. The previous emails seemed to suggest we will.