Hi there @N11
Unfortunately, due to the high demand for the iPhone 8 deal, Optus no longer are doing this promotion for the iPhone, and as such are not doing any more orders for it at this stage. This is what a moderator has said in a different post:
The $59.00 promo plan has been incredibly popular, due to the high volume of order we've received there is a backlog of orders to get through. As of the 22nd, we’re no longer promoting the offer online and have been advised that the iPhone 8 is not available for rain cheque or back order.