Problem Description

Release Burndown is showing data based on the timestamp with association between change items and Sprint. Below scenario will help to explain it:

1. Have a project and board
2. Create Sprint 1 and Story A
3. Assign Story A to Sprint 1 and start this Sprint
4. In Backlog, create Story B and also version 1
5. Add estimation to Story B, assign it to version 1 and complete it.
6. Notice that in Release Burndown, it displays Sprint 1 even Story B never get assigned to Sprint 1

Second scenario:

1. Have a project and board
2. Create Version 1
3. Create Sprint 1 and Sprint 2
4. Create Story A and add estimate
5. Assign Story A to Sprint 1 and start this Sprint
6. Remove Story A from Sprint 1 and assign it to Sprint 2
7. Remove Story A from Sprint 2
8. Assign Story A to Version 1 and complete this Story
9. Notice that Release Burndown shows Sprint 1 even Story A doesn't belong to this Sprint anymore when it's complete.

Suggested Resolution

Improve the way Release Burndown displays data by adding some checking if a Story belongs to certain Sprint. If it doesn't belong to any Sprint, the current Sprint should not be shown into this report.