You can automate set generation as an independent job that is not dependent of an upload.
To automate Image Set generation
Click File > Generate Set.
In the Generate Set dialog box, specify a job name.
By default, the job is given a name that indicates it is a generated job and when the job was generated.
Select the preset that you want to apply.
Click Destination Folder and specify the folder that you want to use.
Click Submit.