Another thing I thought about is that I take Scruffy out EVERY HALF HOUR from basically 6/6:30 until he goes to bed at 9:30, so he loses his water at 7pm, PLUS he goes potty about 5-7 times since he loses his water........my guy (11 weeks) sleeps from 9:30 until anywhere from 5-7 am (it's usually when dh gets up 6am, but occasionally before that), so that is working for us
Good luck, I know I need my sleep, so taking him out every half hour at night is WORTH it to me!!