Once you have made modifications to a batch of items, if you notice you made a mistake, or if there is something more you have to do, you have to start over.  This is particularly annoying if you scanned all the barcodes and are not working from a file.

Technically, you can press the back button and make changes, but you have to remove all the changes made the first time before you make additional changes.

I would suggest adding a button on the results page that says something like "Make more modifications to this batch", which would take you back to these items, but reset all the modification fields for a new set of changes.