In a running multi-year multi-team project there is a set of stories that have been fully estimated and closed, having fulfilled the definition of done. Time has progressed and possibilities in Jira Agile have advanced, making it more useful to group user stories using an Epic to describe the total goal of the set of stories. There are new stories groomed and estimated that belong to these same epics, however the comparison between the old story points and the new story points cannot be made to fit: the new story points are worth less per story point.
Is it acceptable to re-estimate the completed stories, increasing the number of story points that were completed a year ago? What sort of problems may arise from this if the changes are handled as scope changes?
It sounds like you’ve changed the definition, value, sensitivity of a story point (time, complexity, etc), so you’re really doing a conversion and not a re-estimation. Unless there is more to it, it’s no different then changing from entering in days and then changing to hours. Just do the math but it’s really worth the same based on today’s definition.