My ds2 is 16 weeks and I normally change him at feeding time which can be anything between 3 and 5 hours (mostly 3) Although I do tend to do it a bit more often in this hot weather, must be quite uncomfortable. Ds1 who is 21 month has his changed 4ish hours or when feels full or smells, depends how much he drinks, but again is normally more ofte in hot weather.
I still change nappies at night. I stop when they stop waking. My boys are both 'heavy wetters' and I have had a nightmare finding nappies to cope with it. At one stage, I was changing ds1 every hour and half or he'd leak. I use disposables, and the best I've found are Tescos own brand.
Agree re Tescos. However at night I have always had fairly good success with (old fashioned now I know) tots bots cotton with a booster. The baby's bottom doesn't so much look "big" in this but quite enormous though!
I think you need to do what you're comfortable with really. Like I said, I change more often in summer because I can't imagine it's nice sitting in a wet, hot, sticky nappy. I wouldn't worry about it, if your happy changing every few hours then carry on. Or you could leave it a bit longer of you wanted and just see what happens
Two Yes, I do use a fleece liner so her bum is dryer than without but I still feel bad leaving her in a wet nappy. I've never given it any thought before - if wet = change nappy, but something I read on another thread made me think that maybe everyone else leaves it until the nappy is 'full' IYSWIM.