India’s Perform Achieve and Trade scheme has been the mandatory energy efficiency compliance mechanism for Designated Consumers since 2012. The CCTS replaces it as the primary carbon and energy performance instrument from FY2025-26. This analysis maps what changes, what stays the same, what happens to accumulated ESCerts, and how the dual-period transition of 2025-2027 must be managed by entities that were PAT obligated in Cycle 2 and Cycle 3.