Available again for $12, these were quite popular last time.
The following varieties (only) are available at $12 (others are $15):
Lemonade Zero SugarExpired
Lemon Lime BittersExpired
Amazon appear to be matching the VIC Coles 1/2 Price special of $1/Bottle ($12 for 12), however for us in SA/NSW it's $1.25/Bottle ($15 for 12).