28. A contributor on authorized leave of absence without pay for any of the following reasons shall be required, in respect of his absence, to pay the amount that he would have been required to pay under section 36 or 37, whichever applies to him, had he not been absent:
(1) to pursue studies or acquire training from which the Government will benefit;
(2) illness or injury;
(4) personal reasons, if the leave of absence does not exceed 3 months.
In all cases, the employer shall supply Retraite Québec with an attestation stating the reason for the leave of absence.