You don’t need to start completely over. It’s really a simple matter of process and re-upload and process again. If the visual proof in Postalocity shows you are just a little off in alignment, or you need to make a text change, simply go back to your creation program and make the change there. Then save it again, delete the PDF that’s currently in the job, and re-upload the corrected one, then reprocess the job. With this approach, editing should be fast and easy until the proof looks right.