This paper derives a finite-system framework for ambiguity, drift, operational control, bounded memory, substrate inspection limits, and autonomous operation. Starting from finite distinguishability, nonzero state-change cost, and finite throughput, it argues that ambiguous instructions create runtime drift surfaces under selection pressure, while minimum-ambiguity structures move failure from runtime interpretation to design-time verification. The paper presents a hardened theorem core: ambiguity as a finite interpretation set, conditional cheap-path drift, minimum-ambiguity collapse, recursive ambiguity traps, conditional drift-mode enumeration, operational algebra over finite constraints, finite blind-spot formulation for inspectable substrates, and bounded-state memory under explicit assumptions. Later evidence upgrades derive the N-decomposition from FSSTP mode structure, formalize the semantic uniqueness of the seven operational dimensions, derive the inspection-wall framework, and derive the structure of the four control ratios. Companion and support files include ΣΦL v2.2 as the active translation/codebook reference, the AST derivation support supplement for the classical-witness and P2-attractor bridge, and other related late-stack papers on ΣΦL and self-referential convergence.