if they return your application that means it didn't pass the preliminary view, i.e, application incomplete for whatever reason. Although I've seen some applicant who did not receive a letter with their package detailing what missing, yet, most of the time there's a letter in your package which explains what missing in your application. If that's the case, it means the application did not enter the system yet. However, you don't have to pay the $75 processing fee when you resubmit as your receipt is still valid but unfortunately they'll treat it as just received.
i was a July 18 applicant got my application returned on August 31 for country specific requirement, old checklist, and PA photo specs. I've fixed it, resent it a week later and now i'm considered a September applicant.