As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT ENGINE OIL PRESSURE DROPPED AFTER TAKEOFF. AIRCRAFT RETURNED TO AIRPORT. MAINTENANCE INSPECTED ENGINE, SERVICED ENGINE WITH 3 QUARTS OF OIL. TEST FLEW AIRCRAFT FOR 30 MINUTES. PRESSURE CHECK AND QUANTITY CHECKED OK AFTER TEST FLIGHT. THIS ENGINE WILL REMAIN ON MAINTENANCE OBSERVATION FOR THE NEXT SEVERAL DAYS.