From the announcement:
Next week we are launching an Early-war sale covering pretty much every tank, gun, infantry team (as well as a few other things) with an E on it. For a limited time you will be able to buy two and get a third for free. We will also have special pricing on the Early-war books (Blitzkrieg, Hellfire and Back, Burning Empires and Rising Sun) so you can complete your collection or start a new theatre. We are also going to put a cap on the amount you are going to pay for shipping so you can spend more on figures and less on freight.