Rename options in a custom field

The need to rename the options in a custon field. The only options I can find are to delete the old one and add a new option. The problem with this is If I add a new option the custom field, I would need to migrate all issues from the old option to the new one. I cannot find a way to do this, other than adding the new option, then moving the values manually for each issue, then deleting the old value.

Is there a better way?