United Airlines has one of the great heartbreaks of travel — the just-missed connecting flight — in its sights.

In June, the airline announced a tool called ConnectionSaver meant to help more people make their connections without arriving to their destinations late. On Wednesday during an earnings call, CEO Oscar Munoz said the initiative “has already saved over 50,000 customers from missing their connections year-to-date, which is accruing customer gratitude and appreciation over time while ensuring each aircraft arrives on time.”

He highlighted the effort as an example of a customer-service improvement the airline is making.

United started testing ConnectionSaver in February at Denver International Airport, then rolled it out to Chicago O’Hare. In the four months of that early testing period, the airline said, more than 14,400 travelers made connecting flights they would have otherwise missed, thanks to the system. According to United, delays on flights that were held so passengers could rush onboard averaged six minutes.

In June, United said the technology would expand to the rest of its hubs by the fall, and to all airports where it operates “in the future.” A spokeswoman said Wednesday that ConnectionSaver is live at all seven hub airports and would be at all domestic U.S. airports where United operates by the end of October, with plans to roll out globally in the future.

The ConnectionSaver tool uses new technology that automatically flags flights that can be held for connections and sends text messages to travelers with directions to the gate and information on how long it should take to get there. It considers the effect that holding the flight could have on other passengers and flights as well as how long it will take the connecting travelers to get to the plane, and also takes into account airport curfews, crew working hours and whether other planes are waiting for a gate. While the system places an automatic hold on the flights that it identifies, workers can override that delay if there are reasons why it doesn’t make sense.

“ConnectionSaver only works if it allows us to care for as many customers as possible — without inconveniencing others — and that’s exactly what this technology has shown it can do,” Toby Enqvist, United’s chief customer officer, said in the June announcement.

Brett Snyder, founder and author of CrankyFlier.com, an airline-industry blog, said United and other airlines have already looked at data to decide whether to hold flights for tight connections. But those decisions have been made by humans looking at a variety of factors rather than technology that makes the call automatically.

“This is just putting more rigor behind it,” says Snyder, who wrote about the new tool in June. And, he said, it’s a great marketing ploy to contrast United with other airlines.

A spokesman for Delta Air Lines told the Los Angeles Times this year that employees use a mix of software and artificial intelligence to back up their decision to delay a flight; Southwest told the newspaper that its people are the “supercomputers” when it comes to holding flights. An American Airlines spokesman said the airline reviews connections based on factors including crew time and whether a delay will cause additional passengers to miss their connections, and can use automated systems to look at those options.

“It’s helping people, it’s great,” Snyder says. But he wonders whether the travelers who are making their flights only because of the new tool even know it. His suggestion? The airline should send a notification in those cases: “ConnectionSaver to the rescue — you just got saved.”

Along those lines, United spokeswoman Maddie King said the airline is working on “providing an alert that customers will receive that says, ‘Hey, we know you’re running late and the aircraft is waiting for you until this time.’”

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