Some trains will have 8 cars but stop at some stations with only 4 cars worth of platform. The passengers heading to those station usually knowmto board the fir

Some trains will have 8 cars but stop at some stations with only 4 cars worth of platform. The passengers heading to those station usually knowmto board the first four cars. The difficulty arises when doors are accidentally opened for all cars at 4-car platforms. No, the train does not move forwards by 4 cars, it simply stops, passengers board and alight from the front four (including a rush of passengers frommthe back four cars who forgot that their station is a four-car stop), then the train leaves.