What happens if a system scales past the ARC Bound?
Not an instant catastrophe and not a wall. Above the boundary the framework withdraws its guarantee of stable internal self-correction: correction lags, deviations accumulate and compound, and the system drifts from the state it was correcting toward. Whether that ends in external intervention, redesign, saturation or breakdown is an empirical question the framework does not decide alone.
The ARC Bound is a stability boundary, not a physical wall, so crossing it is not itself the catastrophe. It is the point at which the framework's guarantee of stable internal self-correction breaks down. The predicted sequence is mechanical: the system changes faster than it can evaluate and correct its own changes, small deviations that would previously have been caught persist and interact, and the trajectory drifts from the state the correction machinery was holding it to. Falling out of alignment is the consequence; correction failing to keep pace is the mechanism. What happens after that is genuinely open: external controls can halt the process, an architectural change can restore adequate correction, growth can saturate, or the instability can compound. Paper X sharpens the operative question into a race: under accelerating self-improvement the misalignment fraction vanishes only if the correction exponent beta exceeds the drift-acceleration exponent k. That race, not any single number, is the load-bearing safety quantity.