Upon looking over the boat bottom I noticed a hump between Frame 89 and 110. It was noticeably unacceptable when a batten was placed across the top of it.
The cause of the hump is my failure to pull the center-slot in the bottom panel all the way together way back when I stitched the hull together. Above is a photo of the slot taken from the inside of the boat.
For the fix I cut the joint from Frame 89 to 110 and pulled the bottom down
(the boat is inverted right now) with a few windlass. See photo below.
(the boat is inverted right now) with a few windlass. See photo below.
The hump has been pulled down to create a fair line along the bottom.
After the glue cured, the hull is a lot more fair.