Altering the file contents of a backup drive after completing a readynas backup

I have just bought a drive enclosure and SATA drive to perform regular backups from three shares on my RN516 NAS. Two of the backups went as planned, realising that I had to create a target folder on the HDD backup to accept the copied data in each case. You will know how you create  a backup job under OS6, you need to specify a target directory (folder) on the destination drive or else the data files will be dumped in the root directory. This happened to me on the third and final backup job of the day when I was in a bit of a rush. There were only a few items, nested folders, which contained files mainly docs, movies etc.

My question relates to my future plans to do incremental backups. Given Ive  moved the content from the root directory to the intended folder after the fact and of course I’ve adjusted the backup job settings, are any subsequent backup jobs I perform, all incremental backups, likely to succeed or is success predicated on performing a perfectly executed backup first time? I don't know the technical intricacies of a backup procedure which is why Im asking my question here