"Andrew, there are no generalized fixes that work in all cases. The post said some corrective action was already taken.
My comments may be off due to the limited information to base the comments.
Step 1 would be to review your build…"
"It looks to me like the wood is checking, usually due to not being well sealed. Nothing the easiest photo to make comments with. Stress cracks usually occur in fiberglass laminates due to flexing that breaks a portion of the laminate…"