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 REPORTED LEVEL 2 CORROSION ON THE LEFT CENTER SEAT RAIL BETWEEN STATIONS 572.0 AND 664.0. MAINTENANCE REMOVED & REPLACED THE LEFT CENTER SEAT RAIL IAW BOMBARDIER Q400 SRM 51-41-00, 51-42-05, 51-40-15 & 51-40-07. AIRCRAFT IS CURRENTLY STILL OUT OF SERVICE FOR HEAVY CHECK COMPLETION.