Re: Pumping at a late stage for weaning?
I know this probably isn't what you want to hear, but solids don't seem to make babies sleep longer at night. (If they did, we'd all be doing it, trust me! ) Instead of caving in to solids before signs of readiness show up, I personally would try to gently alter the baby's sleep habits. I really liked Elizabeth Pantley's book The No-Cry Sleep Solution- it's very BF-friendly and knowledgable.
That actually doesn't sound "very often" to me, since many breastfed babies feed a lot more frequently that every 3 hours at only 4 months. If your LO often going 3 hours during the day? If so, you might want to encourage her to nurse more during the day, so that she doesn't need to feed as often at night.
My baby now tends to take from both breasts at a feed, and feeds very often, only stretching max. 3 hours.
But if you read all this and you're still thinking that solids is the way you want to go, I would try pumping after your baby's first feeding of the morning. Morning is often when moms find they have the most milk to spare. If that didn't yield enough milk, I would start pumping immediately after nursing throughout the day. At first you might only get a small amount of milk, but if you keep it up, your body will eventually respond to the increased demand by producing more.
Don't worry that pumping will "steal" milk from the next feeding. If it happens that you pump right before your LO wants to nurse again, and you're fairly empty when she nurses, it's still going to be okay because the breast is never entirely empty. Milk is always being made, even as it is removed. Your baby may have one feed where the milk isn't flowing as fast or abundantly as she would like, and she may want to feed again soon after, but she won't be sucking on a dry breast.
Coolest thing my big girl said recently: "How can you tell the world is moving when you are standing on it?"
Coolest thing my little girl sang recently: "I love dat one-two pupples!"