Five days a week, Lori Cash leaves her house when it's still dark out to get to her job at the Depew Post Office in upstate New York.
Cash, a 22-year veteran of the U.S. Postal Service, is responsible for opening post office doors and greeting the waiting delivery trucks at 2:30 a.m.
These days, her early morning work schedule isn't what's causing her to lose sleep, she said. Instead, Cash is troubled by the dramatic changes she has witnessed at the Postal Service, which she said are forcing unprecedented delays in mail delivery.
"In all the years that I've been with the Postal Service, I've seen many changes. I've seen changes in operation. I've seen changes in delivery standards. But I've never seen any mail delay," said Cash, president of the American Postal Workers Union Western New York Area Local 183.
"That has always been our cardinal rule, is to not delay the mail. So to have someone come in and all of a sudden tell us we're not going to deliver all the mail every day is a complete change in the culture that we were taught from day one," she said. "I've never seen anything like it."
Cash and other postal workers say there have been concerning and potentially catastrophic changes in mail delivery since Louis DeJoy took over as postmaster general in June.
In his two months on the job, DeJoy — a longtime Republican donor and ally of President Donald Trump's who held no positions in the Postal Service before his appointment — has overseen major operational changes that he said are aimed at cutting costs and increasing efficiency.
Among the changes: elimination of overtime and instructions to postal workers to set out on their routes even if it means mail arriving later is left behind at distribution centers.
According to postal workers who spoke with NBC News, the changes have upended the mail delivery system and significantly delayed the delivery of items, including express mail.
"If the mail doesn't make it to the dock, it doesn't get on the truck," said Daleo Freeman, president of the American Postal Workers union in Cleveland, who joined the post office ranks in 1994. "So we've had mail that has been left in the plants. Then they get it on the truck the next day. "
Michael Cinelli, a driver for the Postal Service in Long Island, New York, has seen similar delays.
"The way they're stopping it, the mail's just not making it to transportation," said Cinelli, who is a shop steward for the union. "It's just staying where it is. It comes in and it just does not make it."
Cash said a significant number of express mail items, which the post office promises customers will be delivered by noon the next day, aren't arriving on time as a direct result of the new mandates.
Freeman said he isn't certain what the motive for the delays is.
"Maybe it's because of the mail-in balloting. Or maybe it's because [DeJoy is] trying to make sure that they continue on their path to try to privatize the people's post office," Freeman said. "The proof is in the pudding. That's what's I've been telling people. And his actions are speaking."
Cash said she is extremely disheartened to see the number of longtime customers coming to her post office asking where checks and other valuable pieces of mail are.
"We have many more inquiries at the window of customers looking for their packages, wondering why it's taking so long for a package to get just a state or two away, wondering why they're mailing letters or mailing their bills and they're getting there a lot later than they used to get there," she said.
The postal workers NBC News spoke with insist that if the operations hadn't been overhauled this summer, handling mail-in ballots wouldn't be a problem this fall.
"We process more than a billion holiday cards every year," Cash said. "So if we can get those holiday cards through every year and almost all of them are delivered on time, we can handle the election ballots. The problem we're going to have is, you know, Postmaster DeJoy obviously is on this track to make changes right up to the election. So can we handle it? Yes. Is he trying to stop us from handling it? Yes."
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The postal workers say that, beyond the election, they are most concerned about what the erosion of the Postal Service could do to Americans in rural communities who rely on it heavily for critical deliveries, from mail orders to medications.
"I think everyone is feeling the pain of, you know, why are we doing this? Why are we cutting service? And why are we causing such turmoil to our customers?" Cash said. "Everybody is fundamentally watching the beginning of the dismantling of the Postal Service."
Freeman said he hopes postal workers will be given the resources to best perform the duties they take so seriously.
"We want to just do our jobs to the best of our ability and be given the resources to do that," he said.