Blueprint property values ignored in package, inherits parent values

We have 2 blueprints, and in the Blueprint editor we’ve set one as the Parent Class of the other. The parent defines some float variables and some default values for them. The child overrides these defaults with its own values.

This works in Play In Editor mode, but when we create a packaged build the child’s values are not set correctly, and it inherits the parent’s values.

Is this a known issue? We suspected it may be due to bugs in the circular reference handling code, and copying the child blueprint completely (so it isn’t referenced by anything any longer) does work, but we’re worried about the fact we don’t currently have any visibility on when this is happening.