A SI league may be closer than some think. The National League (formerly the ASB) licences are for only two years and then no guarantee there with be a national league after the 2017/18 summer. If my information is correct then at least half of the existing National League clubs are really struggling to find the $ for the entry fee with several still in arears from last season.
Also understand that there is more interest from clubs in the FootballSouth Federation now than has been in the past for a combined league.