As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS NOT GROUNDED AND IS IN CHECK FOR SCHEDULED MX. DURING INSPECTION OF THE AFT CABIN FLOOR 261LG WAS FOUND CORRODED BETWEEN FR66 TO FR 68. REPAIR IS REQUIRED. REPAIR OF 261LG PANEL REFER TO EA#N2-53R-39792 REV ORIGINAL. MX ACTION IS ACCEPTABLE.