Re: Decreasing supply too much?
Block feeding is more of an art than a science. Rather than feeding according to the clock, I would go by how full/empty the breast feels and how the baby is acting. Breasts feeling full + baby acting satisfied after nursing on one side = longer blocks. Breasts feeling empty + baby fussing after finishing the first side = time to switch sides. It's very common to need to block feed for only part of the day, because supply fluctuates over the course of the day. I found that I needed long blocks in the morning and short blocks or no blocks at all in the evening.
Another thing that happens with oversupply is that it can be a "two steps forward, one step back" process. You'll think you have the oversupply tamed, and then it will come roaring back! Just be patient, go back to longer blocks of one-sided feedings, and eventually you should get the oversupply to throttle back again.
It is possible to go to far with block feeding, and to reduce supply too much, so don't feel bad if your oversupply comes back and you continue to have to work on this. My feeling is that it's better to go too slow with block feeding than too fast.
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