Cheddar website lists a deal for $200 Boost SIM plan (140GB) with $30 off using code BOOST170, and $20 cashback within 90 days through Cheddar.
If cashback received, is effectively $150 for the year. Important to note that there's a rumour Cheddar may be shut down, so without further info the $20 cashback may be caveat emptor.
I haven't posted info about Boost network and terms below but can update if needed for members. If the $20 cashback comes in it's the best 365-day Telstra network deal I know of at the moment.
Same as cashrewards?