There are times as a truss designer when you have a job built and something changes in the loading criteria given by the EOR that requires you to rerun your designs.
When this happens use of the "Retain lumber grades/sizes and plate sizes" for rerunning of previously run trusses setting, will come in handy. This will give you an understanding of what will still work and what needs to be sent for a repair or rebuilt.
From Settings\Job Settings\General Tab choose this setting:
Then make your changes to Loading and from iDesign select Analysis\Job rerun loading. You will then be able to see what trusses still work and what ones will need to be addressed further.