Thank you for your reply.
Are you therefore saying that reservation of the bike space is not mandatory given that it is within a hard case box, and that we will be fine providing there is space elsewhere on that carriage? The ticket that I am booking is saying bike reservation is mandatory but I am assuming given it is a box it just counts as a large piece of luggage?
However to guarantee space we will need to book the bike space for CHF 15? Have I understood everything correctly?