Just found a promo for a 12 month licence key for BitDefender Total Security 2015. Basically just pop in your email address and you'll get a 6mth licence. Then the licence will be extended to a 12mth licence in Feb next year based on the email that I received. So a potential saving of $14.58 based on my staticice search.
Edit 1: Looks like the keys don't stack. So if you already using BitDefender Total Security 2015 now, your remaining days on the old keys won't be carried over if you apply the new key. And I don't know if there's any expiration period for the promo key if you don't use them straightaway.
So this is for a 6 month licence?