As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT ENGINE OIL FILTER ADAPTER CAST ASSEMBLY BROKE AT THE FITTING WHERE THE OIL CONVERTER PLATE SCREWS IN. THIS ALLOWED THE OIL FILTER ASSEMBLY TO DROP TO THE SIDE CAUSING AN ENGINE OIL LEAK. SUSPECT ADAPTER COULD HAVE BEEN CRACKED FOR SOME TIME AS IT IS HIDDEN BEHIND CONVERTER PLATE AND IF IT LEAKED IT WOULD GO UNDETECTED (AS OIL DRAINS BACK INTO SUMP).