First, are you given the time of your operation, or the time you’re admitted to your room at the hospital? I’ve been told one by some people and another by others.
Second (and I know this is pretty unlikely, but I’m VERY unlucky!) what happened if for some reason, your train was delayed so long you missed your appointment? Do you lose money or do they just rearrange it? When I asked my PC this she just said “That’s never happened before” which leads me to think the worst! Are the trains booked well in advance of your appointment or is time pretty tight?