4.4.1 and 4.4.2 both run at file-load time, independently of each other and of Run; 4.4.3 runs only on Rebalance Ladder. Built in tandem with 4.3 Build ladder, since both call the same shared sizing engine (ladder-core.js, M5) rather than each carrying its own copy. The amber circles are shared modules (SharedModules.md), not process steps of this diagram.