As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING ENGINE START UP, SMOKE WAS OBSERVED IN THE CABIN AND A CAS MESSAGE FOR LT ENVIRO APPEARED. MECHANIC REPLACED THE ECS FLOW CONTROL AND SHUTOFF VALVE AND RELEASED THE AIRCRAFT. THE NEXT DAY IT NOTED THERE WAS OIL SMELL IN THE AIRCRAFT. MECHANIC INSPECTED THE SYSTEM AND FOUND THE APU TO LEAKING OIL. REPLACED THE APU.