Confusion about Seeding

From the official site ( http://na.leagueoflegends.com/en/news/game-updates/competitive/get-ready-2015-ranked-season[1] ) it says "Your placement will still be heavily influenced by where you ended up last season." So does this mean that it will be basing this at our MMR for the last game in season 4? Or does it mean where we ended up in the pre season?