Any person whose license, permit or privilege to operate has been suspended three times within a three year period by the Secretary of State pursuant to these rules or by a court following a conviction or adjudication of an offense listed herein is subject to a further suspension for a period up to 120 days. The 120 day suspension applies to persons who have been convicted or adjudicated of an offense, which offense was committed following the third suspension within that three year period.
29- 250 C.M.R. ch. 1, § 5