So this evening a train departed Clapham Junction towards Wimbledon and the guard was left on the platform at Clapham. Passengers were stuck onboard at Earlsfield as the driver couldn't open the doors. Train continues to Wimbledon where it was later cancelled awaiting the Gaurd on a following train. How did the train manage to depart without the Gaurd onboard? Surely he/she must have closed and locked all doors and then stepped back onto the platform? Anyone have any more info or ideas as to how this happened?