I agree MN3. We are working to figure out the correct number and inform the sailor. I don't think he is intentionally sailing on the incorrect number and our scoring person may have not been aware that the square top was a modification. Does the material affect the number in any way? Is there a difference between dacron and pentex for instance? We want to make sure everyone is sailing the correct number, especially since some of the members have changed platforms for one reason or another.