A teacher, being a member of the Manitoba Teachers' Society Executive Committee or the Executive Committee of any branch thereof, or of any special committee of the Society, or being appointed as official representative or delegate of the Society or any branch thereof, and being authorized by the Executive Committee of the Society to attend a meeting of the Committee of which he/she is a member, or to act as a representative or delegate, shall be excused from school duties for either purpose or both purposes for not more than a total of five (5) teaching days in any one school year, provided that a substitute satisfactory to the Board can be secured, and that the cost of providing such a substitute is assumed by the Society. A maximum of sixty (60) days in total may be taken for the purposes mentioned above during any school year by members of the Association. Absence from school duties to attend negotiating, conciliation or arbitration meetings shall not be deducted from the above-mentioned sixty (60) days or five (5) days limit. No additional leave of absence beyond the five (5) day or sixty (60) day limits respectively in a school year shall be taken for the purposes mentioned above except with the consent and approval of the Board. Wherever possible the teacher shall notify the Board ten (10) working days prior to taking such leave.