Australia’s largest lender has been forced to swallow a potentially embarrassing defeat in a legal fight over its drive to automate parts of its workforce with artificial intelligence (AI) technology.

The Commonwealth Bank of Australia (CBA) has said it will rehire 45 employees it previously declared redundant. It also apologized for the actions, admitting it “should have been more thorough” before the decisions.

The turnaround comes after the bank and the Finance Sector Union (FSU) of Australia appeared in a Fair Work Tribunal last week over the forced redundancies. They alleged the bank’s “voice bot” had not been the reason for the roles being scrapped. Instead, they were suggesting the bank had used its chatbot launch as an excuse to offload the staff.

It all started when the Commonwealth Bank of Australia informed employees that their positions were made redundant. The employees concerned were told that their jobs were made obsolete because CBA had cut the number of calls received by its call centers.

Staff were assured they were not being laid off because of poor performance, but rather that the “voice bot” had been so successful that it cut calls by up to 2,000 per week. The call volume reduction was a result of an improvement to the AI-powered “voice bot,” launched in May.

Under normal redundancy conditions, employees who accept job offers at Commonwealth Bank are entitled to severance packages of up to $70,000.

The bank also attempted to convince the tribunal that call volumes had “dropped considerably” after the upgrades. This, it claimed, left the bank in a position where less labor was required.

According to the internal documents CBA presented to the tribunal, this left around 450 call center employees “no longer required in the business.” Instead, staff could only “choose to stay and be reallocated in a new role or be made redundant.”

The FSU initially represented the interests of some of the affected workers. In addition to not having their original jobs, they had to rely on their coworkers’ charity to avoid financial ruin. In addition, staff found their pay was docked during the consultation period, even when they were working more overtime shifts to cover the increased work volume.

Union and bank negotiations came to an apparent impasse, so the FSU opted to take the CBA to a fair work tribunal to ensure a more binding resolution.

Documents made public by the tribunal detail the heavy hand the FSU played in cornering the bank into the announcement it made this week. Bank officials had indicated the roles were redundant and had not put forward a more compelling argument.

Appearing before the tribunal last week, CBA conceded that it had made a major error. The bank confirmed it did not account for the rise in call volumes when it calculated the projected labor needs.

One witness had pointed out in the hearing that a sustained increase in call volumes was occurring at the time the redundancies were announced. This was a direct contradiction of the earlier bank claims.

CBA has reversed course, and the affected employees now have three options. They can either accept the redundancy, return to their previous position, or seek another role in the bank.

In statements to Bloomberg, CBA tried to play down the severity of the error while also reassuring staff that the situation would not arise again. “We have apologized to the employees concerned and acknowledge we should have been more thorough in our assessment of the roles required,” a bank spokesperson told Bloomberg.

The FSU has hailed the move as a “massive win” for the members it represented. The union has also used the opportunity to call on banks to tread carefully in their drive for automation.

It has been noted that the impact of the disruption on workers was severe and swift. The workers represented by the union had suffered weeks of uncertainty over their livelihoods.