Members of the Listing Committee may only remain in office for a maximum of six consecutive years in addition to any period of appointment pursuant to rule 2A.24 for the purpose of filling a casual vacancy. A member who has served for the maximum period permitted by this rule may be eligible for re-appointment after the lapse of two years from the date on which he last vacates office. Notwithstanding the foregoing, in exceptional circumstances, the Listing Nominating Committee shall have the discretion to nominate a person for reappointment at any time before the lapse of two years from the date such person vacates office and the Board shall have the power to appoint such person.