52. Detention after date for discharge

Any punishment lawfully imposed on a prisoner under this Act or any rules made thereunder may be carried into effect notwithstanding that the carrying into effect thereof may necessitate the detention of the prisoner beyond the date at which he would have otherwise been entitled to be discharged from prison:

Provided that the period of the detention shall not exceed 48 hours, such period to be calculated from the last hour of the day upon which the prisoner would otherwise be entitled to be discharged.

And provided that no person shall be confined for a longer period than he would have served if he had earned no remission.