Spotted at my local Woolworths. This works out to be half the Bunnings price so it’s a good deal.
Can’t see it on their website but I spoke with the attendant at front counter who said that it’s nationwide.
Here's my receipt with date if anyone wants to take a shot at a price-matching @ Bunnings - https://imgur.com/qnF4gsx
Not sure if they will though because they only stock 20kg bags.