As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UNWANTED FUEL TRANSFER TO CTR TANK. FUEL BACK FEEDING INTO CTR TANK FROM LT MAIN TANK AT RATE OF 1.0- HOUR, TROUBLESHOOTING FOUND THE C-TANK LT BOOST PUMP OVERRIDE CHECK VALVE AT FAULT. REPLACED CENTER TANK LT OVERRIDE JETTISON CHECK VALVE.