Because of our branching strategy, the "Maximum number of commits behind destination branch" merge check does not work for us. We have a branching strategy that puts us square in the BCLOUD-21964 bug. The suggestions from Atlassian have been to make sure that the source and destination branches are not behind our main branch.
If this merge check could be changed to allow us to specify the main branch instead of the destination branch, that could help us out a lot as it would force our developers to keep their feature branches up to date with the main branch.