This just posted on their facebook site.
Not bad, my Sydney to Lima flights were $3570 and now $2855 (Page 3 shows 21% off / $715 discount)
"20% off all economy fares when you fly between 1 January to 28 February 2015, when you book before 13 October 2014. South America has never been closer!
Book here: http://bit.ly/1BD4gFC
*Discount is exclusive to LAN.com. Conditions apply to all fare levels and vary depending on class"
$2855? I hope that's business class!