Seem like SQ is updating the schedule for australia. Or blocking all the awards seats to australia for the time being.
not just F awards. Even business award to SYD/MEL/BNE/PER all are on waitlist.
maybe they are monitoring the situation about the reopening of australia and also does not want to upset customer when the quota is reduced n they have to offload pax (most likely they see an increase in number of paxes making award booking recently for 2022).
so they just put as waitlist. If australia open up, then they can clear some of the waitlist. If australia still impose quota, they will not clear the waitlist.