My DS is 9 weeks old and has been FF exclusively from 2 weeks (couldn't breastfeed 
). From about week 2 he has pretty much got the hang of day and night, going down at 10pm and waking only for feeds and going back down to sleep, and since 6 weeks old has been having bath, feed and cuddle and then going down to sleep at 7pm. He is then woken at about 10.30pm (if hasn't woken before) for a nappy change, cuddle and feed, and then goes back to sleep, usually waking between 3 and 4 am for feed, before going back to sleep until 6-7am.
I know this is really, really good for a 9 week old, but was wondering how we can start to stretch him so he goes until 5am in the night, until he's fully sleeping through the night? His current feeding schedule is as follows:
7am - 180mls
11am- 180mls
2.30-3pm- 150-180mls
6.30pm - 150-180mls
10.30-11pm - anything from 100mls - 180mls (hit and miss depending on how tired he is!)
I guess what I want to know is: am I feeding him the right amounts at the right times, and how much should I be feeding him at his night feed in order to get him to eventually sleep through the night? Not sure whether I should give him a full feed when he wakes at 3-4am, or whether I should give him a smaller one i.e. 100mls then? 
He naps for 45mins-1hr in the morning, 2 hours over lunch, and about half an hour late afternoon.
What do other people do? Not in any big hurry, but would be nice, as i'm often not sure if his 3am waking is habit now or hunger!
Will post this in parenting too!