This system of SF surcharge is collected in many trains Kacheguda MYS express between Bengaluru and MYS, Visakhapatnam Guntur between Vijayawada and Guntur though end to end avg speed is less then 55kmph. Its shoul be implemented to the end station or section station too. For ex KCG SBC is SF which is ok and KCG MYS or Kengeri , YNK MYS should also be non SF.