As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFT DRAIN MAST AFT INTERCOSTAL CORRODED BETWEEN FR86/87 STR27R/28R (C-CHECK RO 6/8/2022) / REMOVED AND REPLACED AFT DRAIN MAST AFT INTERCOSTAL BETWEEN FR86/87 STRG 27R - 28R REF SRM 51-40-08. PART WAS REPLACED WITH OEM PART NO CHANGE TO WEIGHT AND BALANCE. SEE CONTINUATION CARD FOR WORK PERFORMED.