After taking a bunch of measurements of each section of the sail and sketching into CAD, I came up with 89 cubic feet for the pintop and 94 cubic feet for the square top. Could be off but I think 100 cubic feet is a stretch.
I laid the two overtop and took a picture. The square top definitely does not seem like 10-11 more square feet. The luff is definitely curved more to get better shape. Also why it's harder to hoist. All 3 corners and foot line up perfectly. Leach is slightly extended over the entire length.