We have had several versions of Games Workshops new policy with its stores regarding leaked information. This one is the latest regarding the penalty for selling or releasing information on a new release or White Dwarf.
Please remember that these are rumors and such require a bit of salt.
via pauljc on Bols lounge I can definitely confirm that, 'for a period of 6 months, the guilty trade account will not receive new releases until 30 days after the release day.'