Restrictions in Australia appear to be about 88% effective. Should Australia keep going as it is, or ease up somewhat?
Australia could keep the restrictions in place and then the last predictable case using this model could be as early as early May 2020. After that only an unexpected 'spot fire' or cases from overseas would likely need to be dealt with.
Or restrictions could be eased to being 60% effective in reducing the infection rate, and then the last predictable case might be in late July 2020.
It would require a delicate balance, because reducing the restriction from 60% to 54% effectiveness in reducing the viral infection rate would be disastrous, resulting in a prolonged second slow peak. or worse (unless halted by the reintroduction of more effective restrictions).
The number of extra cases that would occur by reducing the effectiveness of restrictions to 60% compared to keeping the restrictions at about 88% is only about 200 extra cases. The reduction of restrictions would be very good for some businesses - but how to do it fairly would be a major problem. Allowing some businesses to reopen, but under strict conditions, would be good for the economy, and not cost a lot in terms of sickness.
The danger would be in the easing approaching anywhere near a 55% reduction in effectiveness of restrictions. That is a narrow margin. Restrictions that are 60% to 88% effective are fine. But to under 56% is a disaster. Obviously it will take a lot of care and perhaps some slow faltering steps to lessen the restrictions but not precipitate a disaster.
The number of cases if 88% effectiveness is maintained peaks at about 6550 cases (orange). And for 60% effectiveness it peaks at about 6750 cases.