Guess its not a mistake as they sent out another email today stating the same thing!
My order with WHSmith says its "ready to send" so hopefully on Monday it will be posted. Will now be cancelling with Play.com and ordering my Sisters Mini from WHSmith.
I understand official partners getting stock first or getting more units but whats strange about Play.com not getting stock until the 1st November is that its owned by Rakuten, the same company that bought Kobo recently.