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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 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.
Note2: It For 2017.01 and earlier it is recommended to use taskTags and workflowIds that are uniquely identifiable by their first 23 characters since those parts of the taskTag and workflowId are used for checking whether a task has already been triggered for a specific T0. When taskTag + workflowId exceed 46 characters the taskTag will be shortened to the first 23 characters and if it then still exceeds 46 characters the workflowId will also be shortened to the first 23 characters. From FEWS version 2017.02 (and 2017.01 after build 73549) will give a warning for this because email alerting might not work as expectedthe shortening is removed, both workflowId and taskTag can be 64 characters long.
Note3: It is recommended to set the interval to 1 second if the action should be executed for every event code (e.g. in the case of sending alert messages), but should be increased if it is not desirable to execute several workflows in a short period (e.g. the case of creating web reports). It also needs the "template task" with the relevant tag scheduled (in suspended mode) as a single/one-off task.
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