Here you go. I bumped the relevant part up from the beginning of the thread:
The mandatory minimum sentence for murder is 15 years, however ...
If "substantial and compelling circumstances" are present to justify a lesser sentence, the court is permitted to deviate from the prescribed sentence as long as the judge provides reasons for the deviation on the record. This is not an unusual occurrence in SA.
In addition to the mandatory minimum sentence, the mandatory minimum sentencing regime also restricts the ability of judges to suspend parts of custodial sentences they impose. The Criminal Procedure Act provides that a court, after it convicts a person for a crime for which a prescribed minimum sentence is applicable, may suspend up to five years of the prescribed sentence on the basis of various conditions, including compensation, community service, submission to correctional supervision, good behaviour, or any other condition that it deems fit. The mandatory sentencing regime prohibits the suspension of a mandatory minimum sentence.
Hypothetically Masipa could reduce the 15 year sentence to 10 if she finds substantial and compelling circumstances (IMO there are none) and then deduct the year already served leaving a balance of 9. In my eyes the minimum he should get is 14, i.e. 15 less 1 year served.