Recursive Bounded Transport Thermodynamics Substrate Physics - A New Transport Frontier Recursive Bounded Transport Thermodynamics (RBTT) - Organized Recursive Geometric Transport Cycles establishes a substrate-level recursive transport ontology operating on the Allen Substrate and Allen Orbital Lattice (AOL). RBTT investigates how recursive admissibility, finite transport capacity, bounded stabilization dynamics, and Hamiltonian-debt redistribution generate macroscopic behaviors traditionally modeled through continuum field theories. Within RBTT, transport rather than geometry is treated as the primitive physical operation. The Allen Substrate is defined as a recursive hexagonal adjacency transport architecture supporting shell organization, PAL continuity dynamics, admissibility accumulation, recursive basin stabilization, and bounded transport progression. The framework introduces: Phase Alignment Lock (PAL) transport continuity, Hamiltonian‑debt accumulation and reconciliation, Basel‑bounded recursive admissibility depth, Quart Chamber stabilization, coheron localization dynamics, Prime Indexed Step Equation (PISE) basin‑transition mechanics, generalized thermodynamic continuity dynamics, and Trishift spectral‑displacement decomposition. Recursive Bounded Transport Thermodynamics (RBTT) replaces curvature‑based interpretation with organized recursive geometric transport cycles operating upon finite recursive admissibility structure. Within this interpretation: continuum geometry is treated as a macroscopic transport shadow, apparent curvature behavior emerges from recursive accessibility gradients, stress‑energy redistribution emerges through debt‑balanced transport reconciliation, and spectral displacement emerges through Trishift decomposition and recursive basin‑transition structure. Accordingly, continuum‑scale theories are interpreted as effective large‑scale projections emerging from deeper recursive transport dynamics operating on the Allen Substrate. The framework derives the Basel Depth Ceiling, D_infinity = pi^2 / 6, as the asymptotic recursive admissibility saturation limit governing bounded transport behavior. The paper further formalizes the Generalized Thermodynamic Continuity Equation governing debt-modulated Phase Alignment Lock (PAL) redistribution dynamics and introduces parameter-free Prime Indexed Step Equation (PISE) falsifiability predictions for prime-indexed spectral-clustering behavior across recursive basin-transition structures. Recursive Bounded Transport Thermodynamics (RBTT) forms part of the broader Pattern Field Theory (PFT) research program and consolidates results extracted from earlier Allen‑Substrate and transport‑substrate investigations into a unified recursive transport ontology.