63Calculation of term of imprisonment

63 Calculation of term of imprisonment (1) Despite anything to the contrary in this or any other Act or in a rule of law or practice, a sentence of imprisonment must be calculated exclusive of any time during which service of the sentence is suspended under section 62(2) or (3). (3) Where an offender serving a sentence of imprisonment is subject to an order made under section 23 of the Mental Health Act 1980 as in force before the commencement of the Mental Health and Related Services Act 1998, the time that the offender is subject to the order or at the hospital counts in calculating the term to be served. (4) Except as expressly provided or expressly ordered, a sentence of imprisonment on conviction on indictment, takes effect from the day the court passes sentence on the offender and a sentence of imprisonment on summary conviction takes effect from the commencement of the offender's custody under the sentence. (5) Subject to section 45(5), if an offender has been in custody on account of the offender's arrest for an offence and the offender is convicted of that offence and sentenced to imprisonment it may be ordered that such imprisonment must be regarded as having commenced on the day on which the offender was arrested or on any other day between that day and the day on which the court passes sentence.