The prime minister dumped the target after Australian medical authorities recommended people under the age of 50 get the Pfizer vaccine instead of AstraZeneca because of blood clotting concerns.
He has conceded not all Australians will get their first dose by the end of the year, even though the government has doubled its order of the Pfizer vaccine.
His decision to ditch the timetable has thrown the rollout into chaos but Jane Halton from the National COVID-19 Commission is calling for calm.
"The trick now is for people just to calm down a little bit and get back to basics," she told Nine on Monday.
"We need to vaccinate the nation, we need to have the vaccines to do that, we're going to get Pfizer at the end of this year and there will be 40 million doses in total of Pfizer."
Opposition Leader Anthony Albanese described the rollout as a shambles.
"Beyond belief that the Morrison government seem to have no idea about vaccination timetables when this should have been their main focus given they have handed most responsibility to the states," he said.
But federal frontbencher David Littleproud defended the vaccine strategy, arguing Australia's progress should not be compared to other countries.
"I don't think any Australian would want the Chinese vaccine or the Sputnik vaccine," he told Nine.
"Australia has been calm and methodical about making sure that we give the best vaccine with confidence, and however long it takes, it takes."
Epidemiologist Mary-Louise McLaws says unless national vaccination rates ramp up to between 100,000 and 120,000 per day, it will take two years for Australians to be fully vaccinated.
The latest daily tally was 27,209.
Chief Medical Officer Paul Kelly has disputed her timeline, arguing daily tallies jump around and the rollout will ramp up significantly once more general practices come online.
Professor Kelly also pointed out vials of Pfizer no longer needed ultra-cold storage throughout the whole process, and local doctors could soon be advised to roll out the vaccine.
The McKell Institute has found vaccine delays will increase the chance of lockdowns and hurt the economy, warning the cost could be more than $1.4 billion.
Trade Minister Dan Tehan will travel to Europe on Wednesday to urge German, Belgian and French counterparts to do what they can to increase vaccine production.
Many of the world's vaccines, including AstraZeneca and Pfizer, are manufactured in Europe. But because of the continent's export controls, it has effectively blocked contracted supplies to countries including Australia.
Professor Kelly conceded the vaccine rollout would be based on international supply deals.
Pfizer has promised the 40 million doses of its vaccine will reach Australia by the end of the year.
"But it will be back-ended at the end of the year, it is true," Professor Kelly said.