ACA Accepted with Errors - How to process a correction?

Hi,

Our ACA files were accepted with errors. I am trying to understand how I correct them. Since this is considered a correction and not a replacement (replacement is for rejected files), do I just edit the same form and manifest files, stamped with the same unique transmission ID and resent, or do I have to rebuild and delete my transmission, correct the errors, and build again for a new transmission ID?

Also, does anyone have any pointers on the TIN Validation Failed error? I understand we have to track down the employee record, identify which of their (many in some cases) dependents had the error, and re-verify with the employee- this will take a while!!