Reserved Shinkansen ticket: can I get on the same train but at a later stop?

If I have pre-booked a discount Hayatoku Shinkansen ticket using SmartEx and linked it to an IC card, can I use this ticket to get on the same train but at a later stop? E.g. I reserved a seat on a train from Tokyo to Shin-Osaka, but my plans change and I want to get on the same train (and same seat) at Shinagawa or Shin-Yokohama instead.