Optus 365 Days Prepaid SIM 280GB for $220 ($320 Ongoing) @ Optus + $100 Cashrewards Cashback

Cashrewards is currently offering $100 cashback on the $320 plan
I am not 100% sure if the Cashback will stack with the $220 deal, but based on the comments from a previous deal it should.
Cashback will likely go down to ~$30 after a few days but not sure exactly when.

$120 for 280GB seems pretty good.