Original story: In a final step of its merger, United-Continental on Saturday performed a massive pr

UPDATED 12:15 p.m. PT: Customers of United Airlines saw improved service on Sunday as the airline worked through technology glitches during its combination of the United and Continental Airlines reservation systems.
On Saturday, United adopted the reservation platform of the former Continental Airlines italy tour operators after the companies merged to form the world's largest airline, now known as United Airlines and owned by United Continental Holdings.
But after spending months preparing for the change — including training about 15,000 employees on the new software — United said on Sunday italy tour operators that technical issues had flared up at airports across the system, causing delays.
"We did have some issues with our kiosks and at times that slowed the check-in process," McCarthy said, adding that the airline's performance had improved by Sunday morning as the company installed upgrades italy tour operators to the kiosks.
About 75.5 percent of United's mainline flights were on time — arriving within 14 minutes of their scheduled slot — on Sunday morning, as were about 87.1 percent of its Express flights, according to McCarthy. "Employees are working hard to take care of our customers," she said.
Original story: In a final step of its merger, United-Continental on Saturday performed italy tour operators a massive procedure consolidating two IT systems into one, a process called a "cutover." The transition has gone relatively smoothly, though some fliers have been affected by missed connections and late departures and arrivals.
Some travelers reported about their experiences on Twitter: "Getting an upgrade on #United has never seemed italy tour operators less convenient or more expensive than it does now. Congratulations guys!," tweeted @rogermud. "Flying on #United or #Continental today? Arrive early as they've italy tour operators completely bungled the debut of their new check-in system. #mergerfail," wrote @owasow. "#United rolled out their new website italy tour operators today and it takes significantly longer to load," @deanwampler tweeted. "If you're flying #United/#Continental today have the option to check in curbside, do it! Reading horror stories but curbside was a breeze," said @ericschmoldt.
In an e-mail to msnbc.com, United Airlines spokesperson Rahsaan Johnson said one system is now supporting the carrier. "The system conversion involves moving millions of reservations and re-establishing numerous communications links. The vast majority of this work is going well, and we are resolving technical issues italy tour operators that we are identifying during italy tour operators this process," he said.
"As a letter grade, I give them a B-," said Joe Brancatelli, frequent flier and publisher of business-travel newsletter JoeSentMe. Most problems, he said, have been reported at pre-merger United hubs such as Dulles International in Washington and O'Hare International in Chicago. Former Continental hubs, he observed, have not had as many problems.
As for the delays at Dulles and O'Hare, Johnson said the airline is working italy tour operators "to speed up airport kiosks, which at times have slowed check-in," but added "most of our flights have either departed on time or within 30 minutes italy tour operators of the scheduled departure time.
As of 5 p.m. ET, United's on-time percentage for departures out of O'Hare was at 16 percent, according to Flightstats.com. Out of 83 tracked departures, one was canceled, 28 were delayed italy tour operators between 15 and 30 minutes, 20 delayed between 30 and 45 minutes and 21 were delayed more than 45 minutes. By comparison, American Airlines' on-time percentage out of O'Hare was 85 percent.
Recent history italy tour operators is littered with cutovers that didn't go quite as planned. italy tour operators Perhaps the most infamous snafu took place in 2007 when US Airways tried to integrate the systems italy tour operators of merger partner America West. The result? Out-of-order kiosks, long lines, flight delays and lots of inconvenienced and angry customers.
More recently, Virgin America and  Cathay Pacific  have suffered italy tour operators IT-migration meltdowns that impacted travelers' ability to manage reservations, access mileage plan accounts or talk to a reservation italy tour operators agent.
italy tour operators As for United's cutover, "people haven't lost a seat or not been upgraded, but it's not running as smoothly as it should," Brancatelli said, adding that problems italy tour operators will be fixed in the days ahead, but said the issue today is moving people through the system.
If you're traveling today, Brancatelli urges carrying on your luggage if you can, printing out everything, leaving for the airport early and allowing plenty of time, and if you're not flying over the next few days, staying off United.com.
United and Continental have gone to great lengths to lay the groundwork for a successful transition. Earlier this week, United's Johnson said the carriers conducted four dress rehearsals, successfully migrating italy tour operators the data from United's Apollo-based system to Continental's SHARES-based one.
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