Constant EDGE_PERIOD 

pub const EDGE_PERIOD: u64 = _; // 6u64

Ticks after which the whole edge schedule repeats: lcm(CPU_DIVIDER, RCP_DIVIDER).

A domain steps when (tick + phase) % divider == 0, and the phases are power-on constants (ADR 0006), so which domains are due at a tick is a function of tick mod this period and nothing else. The fast-scheduler block is exactly one period: its shape is computed once and replayed, which is only sound because this really is the repeat length.

Written as an explicit LCM rather than the literal 6 so that changing a divider cannot leave a stale period behind — a period that is too short would replay a pattern that no longer aligns, silently stepping the wrong domains.