I will be flying into Nice in August and will need to get a train to St Raphael. As I only have a short amount of time in between the flight arriving and the train leaving, I would like to purchase the train tickets online beforehand. However, when booking online you have to specify which time train you need, if I were to the miss the train (plane is late etc) am I able to still catch a later one with my ticket?? Will there be any additional charge??