Hi Kestert. Shelf camp is not a place to be in foul weather, in my experience. One of the scariest nights I've ever experienced was there. Like a cross between an almost-cyclone and a washing machine. Wild wind was coming from all directions, almost flattening our 4 season tent. We took turns during the night to go out of the tent in the horizontal rain to pull back rocks that I could barely lift, that the wind was dragging in, causing guy lines to loosen. There's basically only bog or rock to camp on, and camping on bog causes damage. Tent pegs won't work in it anyway. On the other hand, it's a glorious place to be in good weather.
I'd have a plan B up your sleeve.
The Notch provides a wide range of experiences, depending on the person's scrambling abilities and confidence with a large drop below. First time, going up, I was petrified, and thought I was going to die. Second time, going down, after working solidly on my fear of heights, I enjoyed the scramble, and didn't want to use the rope that was set up. If someone in the party finds Anne hard, I expect they'll find the Notch harder. I wouldn't recommend tackling it in slippery conditions.