Timeline - Option to Hide Completed Tasks

I would like to see the ability to be able to at least toggle the display of complete tasks on the timeline. I have a use case in the way that I’m using Asana it would be beneficial to only see the the incomplete ones.

This ability, and the ability to include sub-tasks, as discussed here https://forum.asana.com/t/timeline-schedule-subtasks/19065 would greatly benefit my adoption of Asana.