Due to works on the trak this train has only seats, because in vroatia the train will not run and there will be a bus instead. 

Why only seats? Beacause this train made by croatian railways and the line is closed. 

Maybe there will be last minute an alternative, but we have no more information.

Wow thanks - very helpful - back to the drawing board

Plan B I can still find places in Sleeper carriage till Villach on the same train looks like Austrian Rail use a replacement trainset between Zürich - Villach Log in your traveldiary Zürich - Ljubljana and book your reservation for Zürich - Villach :)

Thanks so much!  Just starting to make all reservations now for the Summer and this is good to know !

Just one other question if you can help, I have tried to look as far as villa h for the four of us at the end of July but it doesn’t show couchette or sleeper options - do you know if they are available - on the Austrian site I am only seeing seats when I check either option? Thanks again! 

I checked it for just 2 travelers if they doesnt show any option for 4travelers the Cochette and Sleeper carriage is “sold out”