The easiest to use is nightjet.com, but it looks like the train is fully booked on that date.

Couchettes Rome-Munich are available on 7 or 20 April.

The night train Rome-Vienna does have availability on 11 April. It will be diverted via Linz on that day (timetable still has to be adapted), so you could get off there and then take a train to Munich.

If you want to speak someone, it's better to call the operator (ÖBB) directly at +43 5 1717.

You could also consider the La Spezia - Munich night train, running along Cinque Terre in the late afternoon (beautiful) :

- FB Roma Termini - La Spezia 11:57 - 15:50 13€ pp

- NJ La Spezia - München Hbf 17:07 - 09:22 200€ for the 4 people compartment (quite good value for Nightjet nowadays)

The option via Linz would totally work too but it'd probably mean an early start + require a second pass day.

Questions welcome.

Thank you very much. That’s a great help. 
don’t have any idea when the adapted timetable is likely to be published. I’d like to reserve seats on the Linz to Munich leg if possible. 
 

Thanks again. 

Hi @rvdborgt and @thibcabe 

Thanks once again for your help on this. As an update we have adjusted our trip a little to travel to Vienna and stop a night there rather than Munich before heading back to Brussels for a couple of days then home to London.

Good luck with your own plans and hope you have wonderful trips.

Cheers,

Dave