I’m struggling to reconcile your PCB layout with the picture of your 2-wide DIN rail enclosure (over on github). The PCB looks like it has 12 connections along the bottom edge and 10 along the top, while the enclosure has just 6 on each edge (5.08mm apart).
What are the clearances between your L1, L2 and L3 pads? They’re going to have 415V across them. You might want to review this old thread. Not all of it is relevant to your design since you don’t have to worry about a safety barrier, but the 415V termination stuff still matters.