Issue disappears from all reports

Introduction:
We are filtering our backlogs across projects using a customfield called sprint team. Our filters for each board filter for a single team only. Therefore if you change the sprint team for an issue, it disappears from the backlog. Unfortunately it also disappears from all reports!

Example:
Team Rocket has issue ABC-123 in their active sprint. Halfway through the sprint, they realize that they need help from another team and remove ABC-123 from their active sprint. The report shows correctly that ABC-123 was removed from the sprint's scope. After "assigning" ABC-123 to team Balloon, it disappears from their backlog but also from all of team Rocket's reports.

Expected behavior:
The issue has to show up in team Rocket's sprint report even though it is no longer in their backlog. Otherwise it is impossible to see that it was removed from the scope halfway through their sprint.