The following message is displayed on the SA Government website:

As of 14 August 2019 at 11am, Immigration SA is no longer accepting state nomination applications for the 489 visa.

State nomination applications for the 190 visa can continue to be submitted.

A new Skilled Worker Regional (Provisional 491) visa will be introduced on 16 November 2019 and this will replace the 489 visa.

https://www.migration.sa.gov.au/news-events/news-releases/state-nomination-applications-for-the-489-visa-has-closed