Modern cosmology is at a turning point. While the standard ΛCDM model has long been the gold standard, the arrival of high-precision data from JWST and DESI has revealed deep cracks in its foundation—from "impossible" early massive black holes to a 5σ Hubble Tension that refuses to go away. This paper, "Recent Data and Theoretical Developments for MRET/HCC Framework," offers a timely synthesis of these anomalies. It argues that the current "cosmological crisis" is actually the signature of a more elegant reality: that cosmic acceleration is not driven by a mysterious, static fluid, but is a causal, thermodynamic response to the universe’s internal structural growth. By integrating the latest 2024-2026 observational anchors, this work demonstrates how the Mass Redistribution Expansion Theory (MRET) and Horizon-Coupled Cosmology (HCC) provide a unified solution to both low- and high-redshift tensions. We explore how the DESI "phantom crossing" and JWST’s overmassive black hole populations align with a "triggered" acceleration model, anchored by the compelling (though debated) evidence that black holes are cosmologically coupled to the expansion of space itself. This document serves as a bridge between high-level theory and the newest data from our most powerful telescopes, recasting the expansion of the universe as a self-balancing "Cosmic Ledger" that accounts for every black hole formed across the timeline of the cosmos.