Recently we arrived at Termini on our way to Salerno, earlier than expected. We were allowed to pay an increased fare on our previously purchased tickets and catch an earlier train. But if I understand earlier posts, if you miss the train due to your late arrival, you are not allowed to pay the "additional " fee for a later train.
So, always purchase train time you KNOW you can make for the early discounted fare and if you can make the earlier train, pay the increase fare or wait!
Arriving at CDG 7:58 , TVG train to Lyon @ 9:59 and 11:58. The 9:59 could be tight, so I'll buy for later train but can always change to earlier, if seats.
Yes?