change it after warming up the car at normal operating temperatures. no need to wait over night. just drain the old fluid and open the oil pan by opening the oil pan you will drain the extra 1 liter of old oil , after opening the pan wait for 1 -2 hours for more oil to drain as there is no procedure of oil flush in these k310 cvt's . no need to take the whole tranny apart.
1: observe the wear on the pan magnet's if it had more deposits then go for the valve body servicing. it will give your transmission a new life with smooth more power just get the reading analyzed by techstream. for more info you can contact me. one thing more i am starting a new thread relating to valve body servicing's of cvt transmission which restores the power and life back of these transmissions.