They say breaking up is hard to do and it seems New Zealand Post and Kiwibank are no exception.
The Etu union says NZ Post has moved on a fast track in the last three months to shut down around 30 branches it shares with Kiwibank, with 14 set to close before Christmas, putting the jobs of 200 people on the line.
A spokeswoman for New Zealand Post said, with its strategy heading in different direction from Kiwibank, it was an appropriate time to review co-location.
"We will always talk to our staff first about any planned changes, before we make public comment on them. Please note, the majority of the staff in our branches are employed by Kiwibank. NZ Post is responsible for the staff who work in the box lobbies."
She moved to reassure the public that it was committed to providing postal services across New Zealand.
"What we are increasingly doing across our network is looking for local businesses to partner with to help us deliver postal services.
"This is a model that works well for NZ Post, in the climate of rapidly declining mail volumes (approximately 63 million fewer letters in the last financial year), as it comes with less fixed costs, and allows us to maintain a retail network to service our customers across the country.
"This is not a new strategy for us, we have been working in this way in many communities across New Zealand for a number of years now."
However, she said the search to find local businesses could take some time.
"So we would like to reassure the public that postal services will continue to be offered to these communities while these searches are underway.
A Kiwibank spokeswoman said it was not right to say 14 branches were closing.
She said its intention was to open new standalone branches. Yesterday, it announced eight new branches and today another five.
But she confirmed the bank would close three branches in Stoke, Petone and Johnsonville.
She said Kiwibank and NZ Post were two different businesses with two different strategies.
"What our customers want and what their customers need - they are quite different."
The Kiwibank spokeswoman said it had received positive feedback about its standalone branches.
"Customers want in-depth conversations. They don't want to have to stand in a queue to do that."
It already had 14 standalone branches with the latest one opening in Auckland's Henderson this week.
Kiwibank had a total of 234 sites which operated under different models - some were franchises, some corporate stores, she added.
"We are different to other banks in that we have different models."
Joe Gallagher, communications industry organiser for the Etu union, said New Zealand Post had made it quite clear they needed structural separation to happen.
"Kiwibank is going to have to set up standalone branches."
Gallagher likened the situation to a child who had grown up and finished university and its parent was no longer going to pay for it to stay at home.
He pointed to a change made by the National-led Government in 2013 which allowed NZ Post to reduce its number of shops.
Gallagher said NZ Post and Kiwibank had more than 30 shared shops which they were now looking to move on from.
He said some 14 of those were expected to close before Christmas with the remainder shortly after that in what he called an "aggressive timeframe".
"There was a push to do it all before Christmas."
"This has been on the cards for quite a long time."
More than 200 jobs were up in the air, he said.
"Some of those people will transfer over [to the new branches].
But others would be made redundant with work like stamp selling, vehicle registrations and passport documentation franchised into other businesses like bookshops, Gallagher said.
He said the 14 branches were all over the country but expected those who lost their jobs in the regions to be hit harder given they might struggle to find other work.
"Peoples' livelihoods are at stake. This creates uncertainty."
Coming right before Christmas the timing was not good either, he said.
"The commercial world doesn't seem to factor in people's feelings."