SubAnim instances evaluation and root motion

We are experiencing the same issue described here Unreal Engine Issues and Bug Tracker (UE-83410).

Is affecting the root motion extraction since we have two sub instances that provides root motion playing at the same time. Is not really the expected behavior, and the AnimBP debug mode gives little or no information about it.

Does anybody know why is resolved as “By Design”? Which problems may cause prevent ticking the 0 weighted Sub Anim Instance spawned by the Sub Instance node?

Thank you