As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
REMOVED FIRST LOCK FASTENER COLLAR, JUST ABOVE APU STINGER, ON LT SIDE OF VERTICAL STAB AFT SPAR FACE. MECHANICALLY BLENDED CORROSION APX 3 INCHES ABOVE APU STINGER PANEL 342AB. SUBMITTED FINDINGS TO CESSNA ENGINEERING AND PERFORMED BLEND TREAT REPAIR PER TEXTRON AVIATION MEMO DQ10551M1R1 RRL DATED 20 DEC 2017. INSTALLED 1 NEW HI-LOK COLLAR HL70-6 IN SAME LOCATION AS REMOVED.