It sounds like what you are looking for is the concept of variables in timelion which, unfortunately, is not formally implemented today. Timelion does have the concept of variables under the hood, but it is not feature complete or stable, and thus could change at any time.
You can find a bit more context on this in the discussion on the original issue, or follow along with the issue containing current feature request.
Outside of variables, there's no way I'm aware of to avoid this type of duplication.
Hope this helps a bit!