It will be a South Island team. Dunedin has a 26,000 seat roofed stadium and will get 2-3 games a year.They’re marketing it as ‘South Island’ rather than Canterbury, quickest way to alienate the rest of the South Island is to be too Canterbury centric.
Comparison I can think of is the Broncos coming in with Queenslands colours rather than Brisbanes (blue and gold) to try and be Queenslands team rather than just Brisbanes.
Likewise Raiders and Storm went with unique colours vs the regional colours