Kerala will be mostly an hour late when it reaches KPD , it 'll be made to wait at KPD for cheran to overtake. Since Cheran does not stop there and cheran 'll thrash KPD at MPS mostly and it will be ahead by minimum 15 minutes from the time Kerala starts from Katpadi. So catching Cheran itself is difficult for Kerala , palani will be far far ahead. MAS and SA gives priority to their division trains , I have seen Cheran overtaking Kerala at Erode but my co passengers said , that overtake 'll happen at KPD itself most of the times