Take a look: only three trips, for starters...imagine first leaves too early & last arrives too late--you're screwed! Customer-hostile farespic.twitter.com/0ewdyPGTly
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Isn't it funny that it's a problem in the country which charges little in advance then raises the rates close to date of travel? 
France does the same though, indeed the TGV network is pre-booked only.
By pre-booked do you mean you can't buy in stations on the day of travel? Genuinely curious bc it's an ambiguous term...
You have to have a reservation before boarding a train. You can't just jump on like you can here.
In most Japanese stations (and all Shinkansen stations) you can't even get on the platform without a ticket
However, the ticket may be an unreserved ticket (ie, guarantees you passage but no guarantee of a seat), depending on the train you take
Are they fixed time tickets or open tickets? (ie if you miss your train do you have to pay again, or at least queue up again?)
If there's no seat reservation then I think it's open--a seat reservation is for a specific trip, though
So not like the "counted place" reservations on UK Advance tickets where you are tied to a train but lack a seat number?
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