The State must disqualify from operating a CMV for a period of not less than 120 days each person who, in a three-year period, is convicted, as defined in § 383.5 of this subchapter, in any State(s) or jurisdiction(s), of three serious traffic violations as specified in Table 2 to § 383.51. This disqualification period must be in addition to any other previous period of disqualification.