In many time zones, Daylight Savings Time (DST) will move the clock forward one hour in the spring and move the clock back one hour in the fall.
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During all parts of the year, your action will execute at your selected time of day according to the rules of your selected time zone.
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For example:

In the spring, when Daylight Savings Time moves the clock forward, there is an hour that does not exist. Many times this is between 2am and 3am.
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If your action would normally execute during this time period (for example, at 2:30am), then it will execute at the new 3:30am.

In the fall, when Daylight Savings Time moves the clock backward, there is an hour that exists twice. Many times this is between 1am and 2am.
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If your action would normally execute during this repeated hour, your action will execute only once. For example, if your action is scheduled to execute at 1:30am, then your action will execute at the first 1:30am only.
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The exception to this rule is if your action executes using an "hourly" schedule. In this case, your action will execute at both 1:30am times.
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