A teacher being a member of the Manitoba Teachers' Society Executive Committee or of the Executive Committees of any branch thereof, or of any special committee of the Society, or being appointed an official representative or delegate of the Society or any branch thereof, and being authorized by the Executive Committee of which he/she is a member or to act as a representative or delegate of the Society or of any branch of the Society in a matter of Society business requiring absence from school, shall have the right to attend such meetings, or to act as such representative or delegate and shall be excused from school duties for either purpose or both purposes on not more than a total of five (5) teaching days in any school year; provided that the Superintendent is notified prior to the leave, and, provided that a substitute satisfactory to the Board can be secured and that the cost of providing this substitute is assumed by the Society and shall not be a charge upon the Board concerned. No additional leave of absence beyond five (5) days in a school year shall be taken for the purposes mentioned above, except with the consent and approval of the Board.