After 11 years and more than $50 billion the NBN rollout should soon be completed.
But with just 150 days left, some experts doubt the deadline will be met.
NBN Company CEO Stephen Rue dismissed the concerns.
"I think it'll be very hectic, but what I can tell you is we have a run rate of being able to deliver on our projections," he said.
But some experts say delays, difficult-to-connect homes, and a summer of bushfires, make that projection hard to achieve.
"It's fair to say the National Broadband Network will not be complete by the middle of 2020," Professor Mark Gregory from RMIT said.
The NBN Company today reported a $2.1 billion half-year loss, down 25 per cent on last year.
Revenue grew sharply, though, and properties are steadily moving onto the network.
"At the end of December, we had 10.5 million premises ready to connect to NBN," Mr Rue said.
"We have 6.4 million customers on NBN."
But complaints have plagued the rollout, and international comparisons show a tough road still ahead.
Australia ranks 36th out of OECD countries in terms of affordable broadband - last place, according to Commonwealth data released in August.
And on internet speed, Australia ranks 68th - right below Kazakhstan.
Mr Rue said that was due to Australia's sheer size.
"I'm very proud of the network that has been built, which stands up very much in terms of international standards, considering the country we have and the size and geography we have," he said.
But Prof Gregory said the NBN was "most certainly not value for money".
"We've spent $51 billion on a second-rate, 20th-century network," he said.
Source: 9News https://www.9news.com.au/national/nbn-broadband-deadline-unlikely-to-be-met-technology-expert-says/d22a0f45-4420-465a-9fc0-fbe972537fec