Starting my roof repairs tonight (with updates & photos)

Yup, pretty typical for a leaker, that chip board goes away fast when water is continually on it.

From looking at your other demolition pictures, the frame damage is not that overwhelming. I had whole sections of wall that were flapping in the breeze, attached only to the siding. I was lucky the roof didn't blow off on the way home from the seller.

Good deal on posting up pictures, they may prove invaluable to someone following in your footsteps.