Major changes adopted by the United States Postal Service this month could result in slower delivery times for Americans in many parts of the country – prompting outrage, frustration and potential legal action, as experts warn the pace of delivery could plummet to its slowest point in decades.

On Thursday, 20 state attorneys general filed a formal complaint with the Postal Regulatory Commission over the new U.S. Postal Service changes, which were announced earlier this year as part of Postmaster General Louis DeJoy’s “Delivering for America” plan.

The 10-year effort, announced by DeJoy in March, is aimed at increasing the reliability, consistency and efficiency of the United States Postal Service, and seeks to return the beleaguered agency — which has suffered roughly $87 billion in losses over the last 14 years — to profitability once again.

In their complaint, state attorneys general said the U.S. Postal Service advanced these sweeping changes without first obtaining an advisory opinion from the Postal Regulatory Commission – a mistake that “risks the same harms to its stakeholders, including the States and their residents, who continue to rely on the mail, particularly during the resurgence of COVID-19 cases caused by the Delta variant.”

One of the most significant changes involves the delivery time for first-class mail, increasing USPS “time-in-transit” standards by up to two days for mail traveling longer distances. That means, for many Americans, mail delivery could take as long as five days.

In an email Tuesday, USPS spokesperson Kim Frum characterized the service standard changes as a “necessary step towards achieving our goal of consistently meeting 95 percent service performance.”

“With this change of offering 2- to 5-day service based on distance, we will improve service reliability and predictability for customers, while also driving efficiencies across the Postal Service network,” Frum told Spectrum News.

But others disagree, saying the delays will have a disproportionate effect on elderly and poor Americans, as well as those living in rural parts of the country.

“It used to be, in the 1970s, you could deliver things within 600 miles and they'd get there the next day,” said Paul Steidler, a senior fellow at the Lexington Institute who focuses on the U.S. Postal Service and supply chain issues. “The Postal Service abandoned that in 2014, (and) they’ve taken other steps to further slow mail service.”

Steidler added that he believes the impact of the USPS changes will be “very bad.”

“It's going to be especially problematic for people who are on the coasts, or for people who are mailing information long distances from coast to coast,” he told Spectrum News in an interview.

Steidler noted that older Americans – and others without access to a home computer or reliable internet access – are also likely to suffer real harm, and the changes could result in the delay of important items such as bills and credit card payments.

“People who are most impacted from this are the elderly – who are reticent to make electronic payments; those who are in rural communities – (who) are dependent on mail and might not have sufficient internet service; those who are wary of the internet because of ID theft, and also the poor, who simply, in many cases, cannot afford quality computers or internet service,” Steidler said. “So this is a bad proposal for American consumers.”

Already, some Americans say they have begun to see a slowdown in their mail services.

Speaking to NBC News earlier this month, Kimberly Karol, president of the Iowa Postal Workers Union, said residents in her state were “already starting to see the impact” of the USPS changes.

“Under the new system, I’ve seen Priority Mail that used to be a two-day expected delivery time now takes four days,” Karol said. “We’ve had customers expecting medication who have been disappointed because the medications are not being delivered as expected. Some have been very upset.”

The new USPS delivery standards could also face a potential challenge in court.  

This summer, more than 20 state attorneys general submitted a statement of position urging USPSP not to make changes they believe will worsen service for some customers, or repeat mistakes of the mail slowdown seen in 2020.

“I’m deeply troubled by the Postal Service,” North Carolina Attorney General Josh Stein, who signed onto the statement of position, told Spectrum News in an interview this week.

“It’s almost like they’re trying to set themselves up for failure,” he added.

Asked whether he and other state attorneys general plan to take further legal action against the Postal Service, he said: “We are taking a very close look at what the Postal Service is doing to degrade mail service, and whether they have complied with their legal authority to get the sign-on by the postal services commission.”

Experts say the issue at heart is less about procedure and more about the USPS abandoning its core mission. “(I) think that's what the focus has to be (for) a lawsuit going forward,” Steidler told Spectrum News. “It has to be about the fact that Americans – especially the elderly, especially the poor, especially those who are in rural communities – are being disadvantaged by this plan.”

In a filing this summer, attorneys general "pointed out that the Postal Service is chasing after packages at the expense of mail," Steidler said. "And what (the USPS) is bound to do by law, what its most important mission by far is its public service mission: to deliver mail. To deliver not only bills, but government correspondence, legal documents, personal correspondence. Having an organized mail system is essential for the communications of the network of the country.

“This … just seems to go to change the heart of the mission and soul of the Postal Service, which for 200 years has been delivering mail and periodicals,” he added. "Even 15 years ago, packages were a small part of what they did, and they will remain a small part today as well.

“So let me say — I think by January, you have a lawsuit.”