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, MAINTENANCE FOUND LEVEL 2 CORROSION ON THE RIGHT SEAT RAIL AT STATION Y-9.250 BETWEEN X 1.0 - X 71.20. MAINTENANCE REMOVED AND REPLACED SEAT RAIL SECTIONS (2EA) WITH P/N'S 85328210-121 & 85328210-115 IAW BOMBARDIER Q400 SRM 51-42-05-02-01, 51-42-15-02-01 & 51-40-15-02-01. AIRCRAFT IS CURRENTLY STILL OUT OF SERVICE FOR HEAVY CHECK COMPLETION.