I am planning to book a Super Sparpreis ticket from A to C via B, where the A-B leg is on regional (RE/S-Bahn) train and the B-C leg is on a long distance (IC/ICE) train.
Though the Super Sparpreis fare is for train-specific travel, this does not apply to regional trains (emphasis mine):
If you have a super saver fare ticket, you can only travel on the service indicated on the ticket. The offers are available for ICE, IC/EC connections within Germany. You can use local rail services (e.g. RE, RB, IRE and S-Bahn or non-DB trains) to get to/from the long-distance station if you include them in your booking. You are not restricted to travelling on a specific train when using local rail services. However, your journey must be completed by 10 am the following day.
Normally, if a connection is missed due to a delay or cancellation, one can simply use the next train with the same ticket.
But I wonder how this works in this specific scenario, where the regional leg is flexible and the long-distance leg is fixed. Suppose, for example, when buying the ticket, for A-B I select a train leaving A at 9:00 am and reaching B at 9:30 am, and then a train leaving B for C at 10:30 am. Later, I find that there is another A-B connection that leaves at 9:30 am and reaches at 10:00 am, which would leave me plenty of time to take the B-C connection.
Now, what happens if I decide to take this second train at 9:30 am, and it ends up being delayed or cancelled, making me miss my B-C connection? Will I still be allowed to take any subsequent train from B to C, or would I be at fault for not having taken the 9:00 am train from A?
I am not trying to find any loopholes, but I would like to understand how risky it is to make use of this apparent flexibility that is being offered. I can also imagine this scenario occurring in other ways, for example, if I take an earlier A-B connection that goes on a different route, and suddenly gets cancelled at an intermediate station. It would be helpful to know my options if the situation ever arises.
As requested in the comments, the following is an example, where A = Speyer Hbf, B = Mannheim Hbf, C = München Hbf, for 06/12/2022. As an additional note, I get this when I specify a minimum stopover duration in Mannheim (1 hr in this case):