Filming of the revamped show began in Manly, Sydney, three weeks ago, with the new format being pre-recorded rather than live.
As housemates have been in total isolation for that entire period, it's thought they could be in the safest place in Australia.
The Big Brother house is understood to be well supplied with food and essentials.
Coronavirus has been sweeping Australia and has now been given pandemic status.
The update comes after news that Sonia Kruger is confirmed as the host of the all-new Big Brother 2020 on Channel 7.
"Big Brother has spoken and Sonia Kruger will helm the new game. Channel Seven is very excited to have Sonia on board for a thrilling new era of Big Brother," a Channel Seven spokesperson said.
Sonia previously hosted Big Brother between 2012 and 2014, she even hosted the show while pregnant with her daughter, Maggie.
Fans of the show, which made its debut on Australian television almost 20 years ago, will recall memorable moments such as the ‘turkey slap’ and Merlin’s refugee protest.
Big Brother 2020 will return with a new house, new rules and without its live format.
Sonia’s confirmation as host of Big Brother 2020 comes just three months after she announced she was leaving Channel Nine during a teary segment on Today Extra.
Confirming she would be returning to her old stomping ground at Channel Seven, the 54-year-old said in a statement: “I'm beyond excited to be returning to the network where I first discovered my love of live television and family entertainment."