An interlock sentence is a minimum of 12 months.  You can exit this programme when you have completed your allotted sentence time, and complied with the programme.

NZTA will check your reports before you exit the programme, you will need the previous 6 months violation free, OR the previous 3 months violation free AND have completed an alcohol assesment with a preferred provider as specified by NZTA.  For more information visit  http://www.nzta.govt.nz/licence/photo/docs/moh-assessment-centres.pdf