The Exhaustion of Universal Persistence Modes

P103 and P162 established the exhaustive admissibility architecture of persistent identity under real transformation. The persistence problem admits exactly three real primary regimes generated by the two independent persistence conditions Q1 and Q2: Persistence, Transmutation, and Non-Persistence. What remained open was whether the universal sub-regime structure derived within those primary regimes is itself exhaustive. This paper establishes the Universal Sub-Regime Exhaustion Theorem. It shows that once the admissibility structure of LP is fixed, no additional universal persistence mode can arise outside six irreducible structural modes: Flourishing, Fragile Persistence, Directed Transmutation, Drift Transmutation, Collapse, and Dissolution. The proof proceeds in four steps. First, sub-regimes are shown not to constitute additional logical conditions beyond Q1/Q2. Second, any admissible universal differentiation must arise internally within an already determined primary regime. Third, each primary regime is shown to admit exactly one irreducible universal differentiation axis. Fourth, each admissible axis is shown to be universally binary. Therefore the universal persistence architecture resolves into exactly six structurally irreducible universal sub-regimes. This result closes the regime architecture of LP at the universal level. The hedge "currently derivable" used in P162 and P168 to describe the six sub-regimes is thereby removed. Additional persistence modes may exist only as domain-specific realizations within the already established universal regime space.