Hi,
We are using Bitbucket Server v4.11.1 and Bamboo Server 5.15.3 (and JIRA 7.2.4). Projects in all three application are linked together and build related pull request restrictions have been set on Bitbucket (no merging until successful build).
We are on Gitflow - default branch is develop, production branch is master and automated merging is enabled (this have been set on Bitbucket). The repository has been added in Bamboo as linked repository - so basically no manual configuration was done during the setup.
When I check a pull request status in Bitbucket (for example from a Release branch to Master), I can see not relevant builds there also (no problem with the other - Shoredocs - build, the same linked repository referenced in a different build plan too):

So there is a reference to default branch (develop) and a reference to the release branch also. This PR (and all others) are from the release branch to master.
Why was the default branch's build referenced by Bitbucket, if the pull request was from a release branch against the master?
Many thanks,
Csaba