6.11 a) Salaries
In the event that the Employer mistakenly pays a teacher more salary than is provided for in this agreement, or made insufficient deductions, the Employer, upon discovering the error, shall provide proof to the teacher, and a mutually agreed repayment schedule shall be initiated; however, in no event shall the Employer be entitled to collect back beyond 2 calendar years.
6.11 b) Where the Employer has mistakenly paid a teacher less salary than is provided for in this agreement, or has failed to pay any premiums or contributions to teacher insurance or pension plans under this collective agreement, the 2 year limitation shall not apply. In that case, the teacher shall be compensated fully for all monies not properly paid.