Roadmap Feature - Child Level Scheduling Works Only Sometimes

[Lauren Martin]

Trying to set our Roadmap up and having trouble understanding the logic for when child level stories within epics decide to appear on the timeline. I've set due dates, assigned to sprints, and only some sprints show up on the roadmap as well...what am I missing here? 

We've got active Sprints that don't show up in the sprints row and the child stories seem to just randomly decide when to show up. i want to be able to show progress and when those child stories will be finished in relation to an epic/release 

Example Below: Child Story ticket -5264 shows up on the timeline ...that sprint was a completed sprint, we're currently in a new sprint (which doesn't show up on the roadmap either) I've set due dates for everything but not everything shows up...