kct pcb reinforce on a 4-layer mains board placed 57 anchors, but only 16 survive the board's HV class floor of 0.4 mm, the IEC 60664 pairwise table of 1.6 mm between 150 V and 3.3 V, and the 0.5 mm hole-to-hole rule; KiCad DRC flagged 17 clearance errors and some anchors sat on connector and TO-220 pin holes, even though kct route and kct creepage both know these requirements.