If there's already a job in queue or if discovery of that set has already completed, then you can't add or delete a data source to or from a processing set. True or False?

The statement is true because once a job is in progress or if the discovery phase for a processing set has already been completed, the integrity and consistency of that processing set must be maintained. Adding or removing data sources while a job is in the queue can lead to conflicts, data integrity issues, or other complications that could disrupt the processing workflow. This rule helps ensure that processing results are reliable and that the data being analyzed remains stable during the job's execution. The design of such systems often prioritizes the maintenance of orderly operations over the flexibility of modification, particularly when critical processing tasks are in progress. Therefore, it is imperative to wait until the current job has finished before making any changes to the data sources in the processing set.