As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE AIRCRAFT WAS IN FOR HEAVY CHECK, LEVEL 2 CORROSION WAS FOUND BENEATH FLOOR BOARD 252ERF, SURROUNDING THE MIDDLE FORWARD MOUNT FOR THE AFT GALLEY ON THE FLOOR PLATE AT FRAME 87 TO 88. MAINTENANCE REMOVED & REPLACED THE SHEAR PANEL IAW EMB 170/175 SRM 51-42-01 & 51-31-00. REF PO 119412 FOR MATERIAL USED (7475-T761 .063), P/N 170-91919-001. AIRCRAFT IS STILL OUT OF SERVICE FOR HEAVY CHECK COMPLETION.