So if there is a day:
when we have to e.g.: set our clock back from 3am to 2am. Ok.
So if someone creates a cron job at 3am, then if a daylight saving day comes, the backup will run first at 3am, then the clock is automatically set back to 2am, 1 hour passes, then the backup runs again, because it's 3am! [and let's say, that there could be a problem, if the backup runs twice a day. or even worse: no backup will run, because it was e.g.: scheduled at 2am, but the clock never hits 2am, because it will be automatically set to 3am! when we have to set our clocks forward].
so the real Question: Are the daylight saving times are the same around the world, or are they in a different time? Should we take notice of this "theoretical" problem?