I started to wean ash from yaolan since he was about 9 or 10 month old. my 'tactic' was, after he fell aslp in yaolan, i slowly carry him out and place him on our bed and pat him to prevent him from waking up. I keep doing this for few mths. then slowly i let him sleep on our bed or his mattress. Initially he cried very badly and insisted to sleep in his yaolan. at times i got soft hearted and gave in but after that i didnt, just make him sleep on his mattress and after sometime, though he has successfully weaned off yaolan but he still tend to cry abit before napping. Lucky that is just a passing phrase. Since few mths ago, he didnt cry at all when we make him sleep.
fyi, last time we only place him in yaolan during naptime, not night time =)