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Note1: a one off task requires a cardinal time step and a reference time to establish a correct T0 for the run. The new T0 will be the latest valid T0 for the specified cardinal time step. Suppose a task is triggered at 11:59 GMT with a 3 hour cardinal timestep time-step from midnight, T0 will become 09:00 GMT, when triggered at 12:00 GMT, T0 will become 12:00 GMT. The cardinal time step is important as it also controls how often the master controller will run an instance of the task if triggered by an event. It will only run once every cardinal timestep, even though there are multiple events in that period.
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