If the small-car carve-out is dropped, manufacturers that rely on entry-level models will need to rework product mix, powertrain plans, and compliance pathways ahead of the next-year start date. A February-end notification compresses the window for OEMs to lock FY25–26 model updates, supplier sourcing, and certification testing aligned to the new fleet-average targets. The shift would also change competitive economics by reducing regulatory advantage for small-car-heavy portfolios versus larger-vehicle lineups.