Hi, If you miss your connection, due to a delay, you can hop on the next one. In case you had a seat reservation for the train or losing an extra travel day because of the missed train, you can go to the ticket office of the train company at the station to provide you with a free seat reservation/ ticket. More information on delays can be found here. 

Is this information still up to date?

Planning to travel through France to Spain and have to switch trains several times, each train requiring a pricy seat reservation.. what I if miss one of those?! During this time of the year the next train would probably be full already, so how do I just hop on, especially if a reservation is required anyway?..

More importantly: What happens if I miss train B because of delays in train A, have to take an alternative to Train B and will therefore also miss train C, which also requires a reservations?!

thanks :)

This information is correct. Passengers’ rights have not changed. If you miss a connection because of a delay, then the railways must assist you and (if needed) make your ticket or reservations valid for the next available connection. If you think you're going to miss a connection, speak to staff as soon as possible, e.g. already on the delayed train, and ask what to do.

Ach-immer die DE-DB ist ja furchtbar schlecht die letzte 3-4 J in Sachen Verspaetung. Und immer bangen und was waere wenn oder.

Further onward this prob is so minimal that it hardly occurs. And common changes will be held by this national society in FR. The much more bigger prob in FR are the eternal strikes (mouvements social).

If you miss the train for example SNCF trains in france, you can use the same ticket only. You have option to change the ticket before the departure, but if the train leaves take the next train with the same ticket. Just make you sit on the non occupied seats (Just take a seat when train starts running)