As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) "HYD QTY LO C" E1CAS DURING CRUISE. QTY FELL FROM .40 TO .36 BY APPROACH. AFTER GEAR EXTENSION QTY FELL TO 0.28. LHR A/C MTCE.FOUND HYD.FLUID LEAKING FROM CRACK IN CENTRE RUDDER PCU RETURN LINE,LOCATED IN FWD.VERTICAL STAB,AREA IMMEDIATE ACTIONS TAKEN: FAILED SECTION OF HYD.P1PE RETURNED TO B777 FLEET YYZ.