That article isn't trying to imply that the 51,356 cases were all from tests in the last 24 hours.
The actual cases from the last 24 hours was around 31,000.
".....Victoria cases exceed ‘worst case’ limit one week after minister’s assurance ....Victoria’s spike in coronavirus cases has exceeded the worst-case scenario that underpinned the state’s response to the Omicron strain one week after the government insisted daily case numbers would not reach 25,000.
On Saturday, Victoria recorded 51,356 new coronavirus cases as well as nine deaths as Treasurer Josh Frydenberg and former Prime Minister Malcolm Turnbull revealed they had contracted the virus. The government said the record daily result was driven by a backlog of self-reporting from rapid tests on a new reporting platform that went live on Friday.
In total 26,428 rapid test-confirmed cases were reported and 24,928 were diagnosed using a PCR test. Of the rapid test positive cases 20,505 were from earlier in the week meaning the total number of positive cases registered yesterday, through both PCR and rapid tests, was 30,851....Link"
