The problem is that getMergeProposals(merged_revision=...) filters against BranchMergeProposal.merged_revno, via BranchRevision and Revision. It should be able to use BranchMergeProposal.merged_revision_id directly, but that doesn't seem to always be set.
The problem is that getMergeProposa ls(merged_ revision= ...) filters against BranchMergeProp osal.merged_ revno, via BranchRevision and Revision. It should be able to use BranchMergeProp osal.merged_ revision_ id directly, but that doesn't seem to always be set.