Trains in Switzerland don’t need reservations, so you can take any train.

You can add several options to My Trip, then just select which one you actually take.

Thanks. My first time with Mobile Eurail - still on learning curve. 

So I can list multiple trains and I assume I have to select the one train before boarding ? My seat reservation with Swiss I think is non refundable but could I use it on another tarin or would I just forfeit the cost ?

Yes, select the train you’re actually taking, just before you board, by sliding the toggle switch. You don’t need a data connection for that.

(Actually, you can make changes even after boarding, if necessary. But it’s good to do it before, just in case a conductor wants to see it.)

I doubt the seat reservation can be refunded. They’re really not necessary in Switzerland.

Here’s an example from mine - you can see I had two trains lined-up, just in case I didn't make the 20-minute connection at Brussels. In the end, I made it onto the 1825 easily, so I selected that one.

Much appreciated. I’m starting to understand how it all works.

There’s a good primer on the Seat61 website. It’s effectively the instruction manual Eurail should have written!

https://www.seat61.com/how-to-use-a-eurail-pass.htm