Hello Cumboozeerr59
You unfortunately can not exchange or refund any Saver’s or Supersaver’s tickets. Unfortunately, a change of date is considered a refund and new purchase, so you, as per the regulations, do not have the right to any refund. Maybe, if asking nicely at a sales point or via the other SBB contact channels (By phone or Live-Chat) you can get a partial refund as goodwill gesture. Note that the Community is not a way to contact SBB, but a place to get support from more experienced passengers.