I emailed Amazon about this, since they put up another page of England Keep My Bones after I already ordered this copy, that did say it's a signed deluxe edition (with poster). This is what they replied:
~ I have checked with our buying team and they have advised that the first 1,000 orders of this item "England Keep My Bones" will be signed and it also includes the poster.
Your order will be getting the signature together with the poster as the link you gave is the same as the order you have placed. Congratulations. ~
So yes, it does seem that if you already pre-ordered your copy, it will be signed.