This seems to be a revival of this offer. Quoting the page:
Get our $50 Prepaid Mobile Broadband SIM Starter Pack for half price online before 10/01/17 and with 8GB bonus data when you activate before 05/02/17. Data for use in Oz. T&C apply.
Beware that Vodafone had/may still have addressing problems with their shipping, causing problems with delivery. See previous Vodafone online shop deals for reports.
I think you can also get this in 7/11 shops with this deal.
Does not seem to mention anything about unmetered spotify on the page, anyone know if this prepaid has this?