overhangs are 24", and I+W goes all the way up the valleys, 22" to each side of the valleys. The insulation is blown in, and I'd estimate about 20+ inches of it all over the attic floor. Just inside the overhangs, it is filled to within about 2" of the roof sheathing, where I have baffles around the entire soffit. I've checked the roof after a heavy frost and the only spots I can see any heat loss/frost melt is immediately around the skylights.
We are located in Prince George, BC. Let me guess, you saw all the snow and you want to move here from California?
Roofer did show up today and he thinks the water got in at the bottom of a valley where a dutch gable joins the roof. He thinks that ice build up around the bottom of this valley forced water up under the roof overhang at the end of the gable, and leaked in (if that makes sense). He did a bunch of caulking around the flashing and shingles and thinks that should fix it...
If the overhangs are 24", the I&W shield should run along the gutter line by at least 2 rows(66"). If it doesn't, you'll need those cables again.
But like I said, with that climate and that roof pitch, I would have run it up the whole roof.
"They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety."
B. Franklin 1759