A berth could be recorded against one organisation while the port it sits in belonged to another. The two would then disagree about who the record was for: one organisation would see it in its lists, while its edit history sat with the other, and published throughput figures could count work that was not theirs.
This was true of every link between records, not one of them. All 42 now require both ends to belong to the same organisation, and the database refuses anything else.
No existing record was affected — every one was already consistent. The change stops the case arising rather than repairing one that had.