It looks like there's an extra episode present in season 24:
http://www.tvmaze.com/shows/8683/police-ten-7/episodes
Episode 9 is marked as airing on the 4th of may, but according to the official site: https://www.tvnz.co.nz/shows/police-ten-7/episodes/s24 there was no show airing that week.
Episode listing should be:
Ep8 - 27 April
Ep9 - 11 May
Ep10 - 18 May
Thanks!