At NDD 12717 was stopped from 17:02 to 17:26 (24 mins) dont know the reason...
18047 arrived NDD at 17:18 and stopped Departed at 17:37 (19 mins unscheduled halt) only after Ratnachal left..
So Ratnachal got the priority over Amaravathi even when both trains waiting for clearance at NDD station..