When I upload a file to a checklist step, such as a recommendation step, when I save and edit the step again, I see that numbers were added to the beginning of the file name. These were not part of the file name when I uploaded.
These numbers are added automatically by the system in order to avoid having the same file name internally should the file be uploaded to multiple steps or across multiple checklists. The numbers themselves represent the checklist step internal ID. These numbers will not affect the functionality of the file or what the users will see when requesting or submitting the recommendation.