Centrelink appears to have backed down on a plan to open branches half an hour later.
The federal government's welfare agency has since January reduced customer service hours in cyclone and flood-hit areas of Queensland and Victoria.
Opening times in those areas have temporarily been pushed back to 8.30am, from 8am, so staff can process paperwork before serving customers.
But the Community and Public Sector Union told AAP that Centrelink staff around Australia were sent memos this week saying the later opening hours would be extended nationally from Monday, February 14.
Management has now apparently backed down.
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The union's deputy national president Lisa Newman said Centrelink's general manger of people services, Sue Chapman, contacted her on Friday afternoon advising her that Centrelink would not proceed with the later opening hours.
A spokesman for Human Services Minister Tanya Plibersek, however, denied there was ever a plan for a national reduction in opening hours.
Ms Newman said Centrelink staff were worried how aggressive customers would react to later opening times.
"Unfortunately client aggression is already an issue at some Centrelink offices," she said.
"Changing opening hours without notice or consultation is not going to improve things."
