About 200 "stragglers" in the ACT and south-eastern NSW region were yet to swap their mobile phones ahead of the closure of the CDMA network on Monday night.
Telstra has begun a television, radio and print advertising blitz reminding people that CDMA reception will no longer be available after midnight on Monday, April 28.
Telstra Country Wide southern NSW and ACT general manager Ian Peters said people would have up to 28 days to swap their CDMA handset over to the Next G network and keep their existing mobile phone number after Monday night.
People still using a CDMA mobile phone will not be able to make calls, including 000 emergency calls, after midnight on Monday.
Mr Peters said he had been on the road for the past few weeks and spoken to about 1200 people across the ACT region, the South Coast, in Yass, near Young and in Harden about swapping over about 450 handsets.
With 13 Telstra shops in the region, Mr Peters said they only had "a couple of hundred" Next G handsets left. "There's been a heck of a run on them this week, we've had several hundred this week change over," Mr Peters said.
"There'll always be stragglers at the end, there's bound to be someone who is upset because they haven't changed over.
"We are doing this so we can end up with one network and less confusion in the network and much better facilities."
Mr Peters said Telstra shops would be open all weekend for anyone wanting to change over their CDMA phone.
He said the Next G network had seven times the data speed and far superior in-building coverage than CDMA.
CDMA was introduced in 2000 to give digital mobile phone coverage to regional and rural areas after the closure of the analogue mobile network.
For more than nine years the CDMA network formed the backbone of mobile phone services to rural and regional Australians.
At its peak, the service had more than one million customers, most based in rural and regional Australia.
The reliability of the network, and its widespread coverage of about 98per cent of the population, saw CDMA gain support throughout the bush.
Its planned closure in January was postponed by Communications Minister Stephen Conroy until he was satisfied that Telstra could guarantee equivalent or better coverage on NextG. Senator Conroy announced earlier this month that Telstra had reached equivalence of coverage.
Once the CDMA network is closed the remaining digital mobile networks will be GSM, 3G and the newest, Next G.
Telstra said people should return their CDMA handsets to Telstra shops so they could be recycled rather than ending up in landfill.
National Farmers' Federation spokesman Brett Heffernan said a survey of its members revealed increased confidence in Next G.
"Back in January we did a number of surveys of our members to find out how the transition was going. Overwhelmingly it was coming back as a 'no go"', he said.
He added that over the past few months, many of those concerns had been rectified.
"While there are still pockets of problems out there, we are urging farmers to get in touch with Telstra and urging Telstra in turn to fix those problems," Mr Heffernan said.
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