Coronavirus induced changes to Australia Post deliveries the union claim could lead to 2000 jobs cut have been opposed by Labor who is moving to overturn the new model.
The Communications, Electrical and Plumbing Union estimate one in four postal worker jobs could go under the new system which has led thousands of workers to be redeployed to delivery vans or warehouses to cope with climbing parcel demand.
Australia Post has rejected the claims and said no postie will be forced out of work and there were no plans to cut pay.
On Thursday, Labor leader Anthony Albanese said the party would support a disallowance motion in the Senate to overturn the changes implemented by the government in April which are currently due to end in June 2021.
"These cuts are to jobs, these cuts are to services that are absolutely essential," he said.
"In particular, older Australians really rely upon their postal services."
Mr Albanese claimed the government was using the crisis as an excuse and criticised the regulatory changes implemented without public debate.
"This is a government that should be using this period to think about how they can create jobs, instead they're looking at how jobs will be cut."
In a statement, Australia Post said the government temporarily adjusted performance standards to put posties "where we need them most, parcel processing and delivery."
"Their role delivering letters is increasingly falling and with many delivering on their motorbike, they are restricted in how many parcels they can carry safely," it said.
Under the new model, more posties would move to vans and warehouses, priority letter services would be suspended, letter deliveries moved to every second day, and five days would be allowed for intrastate posting.
CEPU NSW/ACT branch official Dennis Williams said Australia Post had already started to cater for increased parcel demand and were using the coronavirus pandemic to "try and cut down the staff to make more profit."
Electric delivery vehicles, recently rolled out in Canberra, were part of that transition, Mr Williams said.
Branch official Cade Anderson said there was angst and concern among members who weren't sure if they would keep their job.
"When they've been the forefront essential service workers during the pandemic to then turn around and be treated in this way is nothing but disgusting," he said.
