Final answer:
The time frame for a driving school official to notify the commissioner after a student fails to complete behind-the-wheel instruction depends on individual state regulations, therefore, one should check with the local DMV or equivalent authority.
Step-by-step explanation:
If a student fails to complete behind-the-wheel instruction, the correct procedure according to most regional laws is that the official of the driving school must notify the commissioner of this event within a specific time frame. Typically, the answer will depend on individual state regulations or policies for driving schools. However, without specific jurisdictional context, it is not possible to give a definitive answer to when an official of the driving school should notify the commissioner if a student fails to complete behind-the-wheel instruction. It is essential to check with the local Department of Motor Vehicles (DMV) or equivalent authority to find out the regulations that apply to the relevant state or region.