Some iPhone users in the U.S. are complaining their phone's clock did not correctly adjust to the daylight saving time change, where clocks officially were moved one hour ahead early Sunday morning.
Users reported several variations of the problem, with some phones failing to jump an hour forward while other jumped forward and then jumped back.
The "date and time" preferences on the iPhone can be set to "automatic," which calibrates the time to that of the operator that provides service to the phone. Users can also opt to adjust their time settings manually, although the software is programmed to account for daylight saving time depending on what region the phone's owner has selected is their approximate location.
"I have a Verizon Wireless iPhone 4 and the time didn't change for daylight saving time today," wrote one user, "ekcwmi", located in Lake Hartwell, South Carolina, on Apple's support forum. "It is set to do it automatically, and I also tried to sync it to see if it would change but it didn't. Any advice?"
Another user wrote in response that rebooting the phone fixed the issue. Someone else wrote that disabling the automatic time update from Verizon resulted in the correct time displayed. When the automatic setting was re-enabled, however, the time dropped back by an hour.
A user going by the name of Larry Finch wrote that phones in "airplane mode" -- which turns off all of the phones radio transmitters -- would not be able to get a carrier time update. "My AT&T phone did receive it, so this is likely a Verizon issue or your phone was off or off net," Finch wrote.
Whatever the cause, the latest problem is at least the third time iPhone users have seen trouble with their devices adjusting to daylight saving time.
Last November, a bug in the iPhone's operating system resulted in alarms going off an hour late as Europe set the clocks back one hour for daylight saving time. Just a month or so prior, the failure of some iPhones to account for the time change caused alarms for users in New Zealand and Australia to go off an hour early.
European countries are scheduled to set the clocks ahead at 1 a.m. on Sunday, March 27, with the exception of Iceland.
Apple officials contacted in London did not have an immediate comment.
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