Problem Definition

When an issue that's in a backlog gets moved from one project to another the sprint will come with it. That causes a lot of confusion if sprints are not being tracked across projects as the sprint will exist on both boards and changing one will change the other. In addition it's not possible to start the sprint unless you have administrator access across both boards and projects.

Suggested Solution

It's a tricky one to solve - but perhaps making the sprint field visible on the move issue process will make end users more likely to remove the sprint value.

Workaround

Manually remove the sprint value yourself.