Steps to reproduce:
- create a pull request with source from branch A and destination to branch B (suppose the commits to be merged contain issue key ABC-123)
- synchronize the repository so that the commits to be merged are recorded and the PR is associated with issue ABC-123 on the Development panel
- update the pull request to change destination to branch C, so that the commits with issue key ABC-123 are no longer in the list to be merged
- synchronize the repository
- expected: the PR is disassociated with the issue ABC-123.
- actual: the PR is still associated with the issue ABC-123.
Workaround: Do a full synchronization on the affected repository from the "DVCS Accounts" page.