We have boards separated by a Team field. None of the issues are overalapping between boards. When I change the active sprint name in Board A then the active sprint in Board C gets changed and vice versa. When I change the active sprint name in Board B then the active sprint in Board D gets changed and vice versa.
If it helps, the filters for each board are as follows:
Board A: project = XXX AND IssueType in (Story, Bug, Test) AND Team = A AND (fixVersion in unreleasedVersions() OR fixVersion is EMPTY) ORDER BY rank ASC
Board B: project = XXX AND IssueType in (Story, Bug, Test) AND Team = B AND (fixVersion in unreleasedVersions() OR fixVersion is EMPTY) ORDER BY Rank ASC
Board C: project = XXX AND IssueType in (Story, Bug, Test) AND Team = C AND (fixVersion in unreleasedVersions() OR fixVersion is EMPTY) ORDER BY Rank ASC
Board
project = XXX AND IssueType in (Story, Bug, Test) AND Team = D AND (fixVersion in unreleasedVersions() OR fixVersion is EMPTY) ORDER BY Rank ASC