It is the same as the other bug you reported (for the same reasons).
I didn't go into the full detail in the other report (as I don't think I remembered all the details at the time), but it's important to note that the behavior there is rather particular to the workflow you listed. Specifically, the fact that the child style is being re-created after the changes to the parent. This causes us to not be able to directly track the dependency information.
If you create a property in the parent, customize it in the child and then edit various properties in the parent (display order, value params, etc), this will be reflected in the child. It's the import part which causes issues.
Is this a common workflow for you (or an issue you've commonly seen with your customers)? I would normally assume that people update the parent style, which would push the changes to any children. It sort of seems specific to having a child export installed on a newer version of the parent.