Bounding Horizon-Activated Effects in Möbius Cosmology with Existing and Near-Term Data

We translate the precision of current and near-term observational programs into conservative upper bounds on the horizon-activated deviation channels admitted by Möbius Cosmology. The analysis is deliberately non-expansive: no detection claims are made, no parameter values are inferred, and no new dynamical assumptions are introduced. All statements remain strictly within the exact reduction and activation structure established in earlier work, in which the Einstein field equations remain exact everywhere and any departures from standard predictions are confined to compact, horizon-adjacent junction neighborhoods through modified junction conditions. Continued null consistency with General Relativity and ΛCDM is interpreted as a tightening constraint on the allowable integrated magnitude of localized junction activation. The result is not persuasion, but measurability.