DT647/648 UNDERSHOOT CORDING TO RS EVENT LOGS, CONSIST 1647 AVERAGE BRAKE CYLINDER PRESSURE NORMAL. FAULT TIMINGS ARE 1812H-1825H. PLEASE KINDLY FOLLOW UP. ~~~~~ DT647/648 UNDERSHOOT        #1647 BCP abnormal,stuck brake during B1 to coast. Replaced ACU and carried out brake & cyclic test-ok. ACU--New s/n: 1442-037  Old s/n: 1450-062 Not: 2126408 raise to RSW. Done by Kalees. 31/01/20