LAN release their seat 330 days in advance on International routes. On domestic it depends, sometimes 330 days in advance, sometimes 10 months, you need to check on LAN (Lanpass account is required) and look for the lowest award level. On long haul or international routes, the award for partners will be available for 1 to 3 days, after that time, you have to check every single day and sometimes twice a day.