Alarm clock is interesting. If I set my alarm to wake me up at 7am, then I want it to run at 7am, no matter what DST changes. On the other hand, I know people who needed an alarm "exactly 24 hours from now", and that alarm shouldn't change to "25 hours from now" or "23 hours from now" just because of DST (think of a chemical experiment where something is mixed and needs to be checked exactly 24 hours later).
Now this problem here is different. There is no excuse for crashing because of DST. I remember a few years ago some game console crashed on February 29th, I think. The crashing code was shown, and within ten lines of code the programmer had written two different ways to figure out whether a year was a leap year, and one way gave the wrong result. So within ten lines of code the software was (a) convinced that Feb 29th was a correct date and (b) convinced that Feb 29th was _not_ a correct date, and then got itself utterly confused.
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With the explanation given (something getting confused with a DST change), the problem would have gone away, and come back in exactly six months or exactly twelve months, but only for one day.