The Australian Border Force is preparing for "surge deployments" of its officers as widespread strike action by officials around Australia next week threatens to open up gaps in its operations.
As unions prepare for the most disruptive round of strike action yet to hit the nation's airports, public service middle managers from the Department of Immigration and Border Protection are being rushed into uniform and into front-line roles.
The main public sector union says the Border Force is using "heavy handed" strike-breaking tactics against its own employees with the union advising members that they cannot be forced into joining "surge" activities.
But the department says it routinely moves workers around to meet its needs.
The DIBP's 13500 workers are currently voting on a pay proposal of 3.4 per cent over three years, one of the lowest on offer in the public service, with Customs officers who have transferred to the Border Force to be hit hardest by the loss of allowances and entitlements.
The ballot was dogged by technical glitches on its opening day with the voting system freezing and crashing as thousands of public servants tried to cast their votes.
The results of the ballot are due on Monday but large-scale strike action is planned for international airports next week with peak-hour stoppages set to take place twice-a-day and serious disruptions to travel expected.
The Border Force has already issued warnings to international travellers to arrive at airports well ahead of their scheduled departures as the actions proceed between September 21 and 23.
Community and Public Sector Union National Secretary Nadine Flood was scathing on Thursday of the plans for the surge deployments.
"This is highly unusual for the Australian Public Service," she said.
"What we have here is Border Force management turning their heavy-handed tactics on their own staff.
"This approach of using managers as strike breakers is causing plenty of angst and division.
"Typically they're bosses, executive level managers or above, who work in head office roles.
"The CPSU has been calling on managers not to get involved in strike breaking, also known as surge activity."
Ms Flood said the scale of the strikes planned for next week was "unprecedented".
"We're looking at an unprecedented round of stoppages at airports in peak periods with short strikes twice-a-day," she said.
The union leader said she believed yes vote to the deal on offer was very unlikely.
"We're expecting a very strong no vote," Ms Flood said.
"This is the worst offer of any Commonwealth agency, which is really saying something."
A DIBP spokeswoman said on Thursday that departmental workers were routinely moved around as needed.
"The Department employs a flexible and deployable workforce," she said.
"Staff are routinely deployed between functions to meet operational requirements dependent upon available resource and priority.
"These arrangements also operate for periods in which PIA has been notified.
"The majority of surge deployments are being undertaken at a local geographic level with supplementation from other locations as required."
Agriculture and quarantine workers are preparing to join their DIBP counterparts in striking at international airports next week.
Human Services, Tax Office, Australian Bureau of Statistics staff other agencies who are in dispute are also planning more half-day strikes around the country.