How do I "append" a new Sprint # to an user story that is in Ice box of previous Sprint

[Chaithanya Anumanchi]

Hi , Consider I am running Sprint 10 and I have an ICE BOXED user story in it. I want to add Sprint # 11 to it , meaning I want to move the story to Sprint # 11 . However , I want to append Sprint # 11 value to Sprint #10 , rather than deleting Sprint # 10 and keeping only Sprint # 11 . How can I append , Sprint #11 to Sprint # 10