As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE OUT OF SERVICE IN HEAVY CHECK, MAINTENANCE FOUND AFT CABIN FLOOR WEB BETWEEN FR87 AND FR88 LBL 35 CORRODED. MAINTENANCE REMOVED AND REPLACE SHEAR PANEL IAW SRM 51-40-08. THIS AIRCRAFT REMAINS OUT OF SERVICE FOR DURATION OF THE HEAVY CHECK COMPLETION.