Useful life.
(15) Useful life. A period of time/mileage as specified in part 86 for a nonconforming vehicle which begins at the time of resale (for a motor vehicle or motor vehicle engine owned by the ICI at the time of importation) or release to the owner (for a motor vehicle or motor vehicle engine not owned by the ICI at the time of importation) of the motor vehicle or motor vehicle engine by the ICI after modification and/or test pursuant to 85.1505 or 85.1509.