Yep we did what Miss E does. Jazz 'slept through' 9pm to 4am from 8 weeks to 4 months, and I'd feed from one side and express the other. If you don't want to, or have trouble, expressing, don't hesitate to wake her up. You don't have to wake her up too much, just enough for her to latch on.

I assume your boobs would get used to it, but I'm not really sure since I expressed. Oh and I got AF back at 8 weeks but she disappeared for a few months once Jazz started waking through the night again.