As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BNA INFLIGHT T1531/21AUG - NUMBER ONE ENGINE OIL CLOG LIGHT ILLUMINATED DURING CLIMB. REDUCED NUMBER ONE ENGINE TO IDLE AND RETURNED TO BNA AND LANDED WITHOUT INCIDENT. FOUND METAL IN OIL FILTERS. REPLACED NUMBER ONE ENGINE ON 22 AUG AT BNA. SYSTEM GROUND CHECKED NORMAL OPERATION.