On this day: Jan 21

The point at which numerical reproducibility (determinism, tensor-hashing debugging) made the release headline. A sign that the training stack is moving from a performance race to a debuggability phase

The symbolic starting point of the private AI infrastructure capex cycle

This is the promulgation date, not the effective date. The addenda set a 1-year grace period, so it must be kept distinct from the Jan 22, 2026 entry into force