To handle daylight saving time JobScheduler works in the following manner:
Change from winter to summer time at the end of March
Jobs / orders planned between 2 a.m. and 3 a.m. will be processed one hour before they planned to avoid that one start time is omitted. That means, a job planned at 2:10 a.m. will be shifted to 1:10 a.m. at the last Sunday in March.
Change summer to winter time at the end of October
Jobs / orders planned between 2 a.m. and 3 a.m. will be executed twice, therefore it is recommended to plan the start times outside this range, if the processes will be run at Sunday.
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Starting with version 1.5.xxxx the time model of JobScheduler changed to UTC time. It works with a continious time ray, therefore problems with dayligt saving time described above are excluded.
The version 1.5.xxxx is currently (January 2013) in beta status and will be released soon.
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