Some travelers reported about their experiences on Twitter: “Getting an upgrade on #United has never

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 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 red lion hotel denver preparing for the change — including training about 15,000 employees on the new software — United said on Sunday that technical issues had flared up at airports across the system, causing delays.
red lion hotel denver "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 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," red lion hotel denver she said.
Original story: In a final step of its merger, United-Continental on Saturday performed a massive procedure consolidating red lion hotel denver two IT systems into one, a process called a "cutover." The transition has gone relatively red lion hotel denver smoothly, though some fliers have been affected by missed connections red lion hotel denver and late departures and arrivals.
Some travelers reported about their experiences on Twitter: "Getting an upgrade on #United has never seemed less convenient or more expensive than it does now. Congratulations guys!," tweeted @rogermud. "Flying on #United or #Continental today? red lion hotel denver Arrive early as they've completely red lion hotel denver bungled the debut of their new check-in system. #mergerfail," wrote @owasow. "#United rolled out their new website 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 red lion hotel denver millions of reservations and re-establishing numerous communications red lion hotel denver links. The vast majority of this work is going well, and we are resolving technical issues red lion hotel denver that we are identifying during 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 red lion hotel denver 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 red lion hotel denver "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 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 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 is littered with cutovers that didn't red lion hotel denver go quite as planned. red lion hotel denver Perhaps the most infamous snafu took place in 2007 when US Airways tried to integrate the systems of merger partner America West. The result? Out-of-order kiosks, long lines, flight delays and lots of inconvenienced and angry customers.
More recently, red lion hotel denver Virgin America and  Cathay Pacific  have suffered IT-migration meltdowns that impacted travelers' ability to manage reservations, access mileage plan accounts red lion hotel denver or talk to a reservation agent.
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 will be fixed in the days ahead, but said the issue today is moving red lion hotel denver 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. red lion hotel denver Earlier this week, United's Johnson said the carriers conducted four dress rehearsals, successfully red lion hotel denver migrating the data from United's Apollo-based system to Continental's SHARES-based one.
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