(6) The time during which a person is absent from a Borstal Institution under such a licence shall be treated as part of the time of his detention in the institution: Provided that where that person has failed to return to the institution on the licence being forfeited or revoked, the time which elapses after his failure so to return shall be excluded in computing the time during which he is to be detained in the institution. (7) A licence under this section shall be in such form and shall contain such conditions as may be prescribed by regulations made by the Secretary of State. [Sidenote: Supervision after expiration of term of sentence.] 6.--(1) Every person sentenced to detention in a Borstal Institution shall, on the expiration of the term of his sentence, remain for a further period of[4]six months under the supervision of the Prison Commissioners. (2) The Prison Commissioners may grant to any person under their supervision a licence in accordance with the last foregoing section, and may revoke any such licence and recall the person to a Borstal Institution, and any person so recalled may be detained in a Borstal Institution for a period not exceeding[5]three months, and may at any time be again placed out on licence: Provided that a person shall not be so recalled unless the Prison Commissioners are of opinion that the recall is necessary for his protection, and they shall again place him out on licence as soon as possible[6] and at latest within three months after the recall, and that a person so recalled shall not in any case be detained after the expiration of the said period of six months' supervision. (3) A licence granted to a person before the expiration of his sentence of detention in a Borstal Institution shall, on his becoming liable to be under supervision in accordance with this section, continue in force after the expiration of that term, and may be revoked in manner provided by the last foregoing section. (4) The Secretary of State may at any time order that a person under supervision under this section shall cease to be under such supervision. [Sidenote: Transfer of incorrigibles, &c. to prison.] 7. Where a person detained in a Borstal Institution is reported to the Secretary of State by the visiting committee of such institution to be incorrigible, or to be exercising a bad influence on the other inmates of the institution, the Secretary of State may commute the unexpired residue of the term of detention to such term of imprisonment, with or without hard labour, as the Secretary of State may determine, but in no case exceeding such unexpired residue. [Sidenote: Treasury contributions towards expenses of societies assisting, &c. persons discharged from Borstal Institutions.]