LOGic DOES NOT depend on the prefix table for DXCC reporting and tracking. You could track and report DXCC with no prefix table at all. You would have to manually log the DXCC every time, but it would work.
All the prefix table does is automatically fill in the DXCC field when you log a call. LOGic has the most sophisticated prefix table in the industry, and additionally uses the BIG CTY from AD1C for the exceptions to the prefix table.
https://www.country-files.com/big-cty/
If a QSO has the wrong DXCC logged, simply change it to the proper DXCC. If you have a thousand, it is possible to clear out the DXCC fields and let LOGic fill them in again. This could be done only before a specified date. Let me know & I will post the details.
Tnx & 73,
Dennis WN4AZY
PS: There are some test lookups to try at
https://www.country-files.com/big-cty/ (use the Info window in LOGic) They are all correct except for UI9XA. It shows up in LOGic as Asiatic Russia, not European Russia as the web page says it should. This is their mistake. UI9XA does not appear in the big-cty file, at least in the version currently available.