WITH ≥1col floor: 24 blocks
  R67 H 4DL members=[5, 7, 28, 34, 42, 48, 50, 67, 68, 73, 74, 80, 100, 102, 107, 127, 135]
  R121 H 2DL members=[12, 14, 21, 39, 59, 111, 116, 121]
anchors: R23,R67,R81,R85,R87,R89,R90,R91,R93,R94,R95,R96,R97,R98,R101,R103,R108,R118,R119,R121,R122,R128,R131,R132