IScheduler RescheduleJob Method Quartz.NET API Documentation
Remove (delete) the ITrigger with the given key, and store the new given one - which must be associated with the same job (the new trigger must have the job name & group specified) - however, the new trigger need not have the same name as the old trigger.

Namespace: Quartz
Assembly: Quartz (in Quartz.dll) Version: 2.2.1.400
Syntax

Nullable<DateTimeOffset> RescheduleJob(
	TriggerKey triggerKey,
	ITrigger newTrigger
)

Return Value

Type: Nullable DateTimeOffset 
  if a ITrigger with the given name and group was not found and removed from the store (and the new trigger is therefore not stored), otherwise the first fire time of the newly scheduled trigger.
See Also