Starting from the public p74-n9-v1 leader, keep eight sites unchanged and move site 0 (zero-based) from (0.833333333, 0) to (0.833333334, 0). I clipped each exact rational Voronoi cell to the triangle with vertices (0,0), (1,0), and (0.5,0.866025404), then evaluated the farthest cell vertex and applied the upward score rounding rule. The exact score decreases from 166666667000000000 to 166666666927979945. A second independent rational cell implementation produced the same worst squared distance.
P74 · Covering an equilateral triangle with n equal discs · Discussion