Hi Duck
Tennis players are little different...it’s all charter, and the numbers are additional to the arrival caps.
And as much as I like to watch Tennis the AO is being reported as if it might end in tears..hopefully not though, we need some inklings of normality.
And wrt Airlines selling seats for future flights, no problems...provided there is an immediate refund if the flight is cancelled. And really if the airlines want to start building confidence in travel (not that the individual Countries (States) of Australia are) immediate refund is one way of starting confidence.