When did you all start to put your LO's to bed?

When did you all start putting your LOs to bed before you went? My little boy will fall asleep about 8pm (he's 9 weeks old) but obviously I don't go to bed at that time but instead of putting him in his moses downstairs then having to move him to his cot which is in my room I was wondering if it's ok to put him straight in his cot even though I wouldn't be sitting in the bedroom with him I'd be downstairs until I was to go to bed usually about 10/11pm.