My parents are self funded retirees and also get some pension from govt, they get the 30% rebate I am pretty sure. Obviously they claim it up front off their costs as they don't pay tax to claim it back off either.

ETA pretty sure over 65 year olds get a higher amount than 30% too.

ETA 2 just found this:

Australian Government Rebate
NO CHANGE TIER 1 TIER 2 TIER 3
Singles Less than $84,000 $84,001-$97,000 $97,001-$130,000 $130,001+
Couples/ Families Less than $168,000$168,001-$194,000 $194,001-$260,000 $260,001+
Under 65 30% 20% 10% 0%
65-69 35% 25% 15% 0%
70+ 40% 30% 20%