From this topic here
https://support.atlassian.com/jira-software-cloud/docs/customize-your-view-on-the-roadmap/
We understand that all of the sprints will show up under the roadmap but it isn't. Every month we have two different sprints for each smaller team(TSO and SIS). When we enable the roadmap feature, only the SIS sprint has shown on the roadmap schedule, TSO's sprint doesn't.
Sprints that have both start and end dates, and are associated with the board will be listed at the top of the roadmap, along with the months
Do you know what it means?
Schedule bars: Each bar represents how long your tasks are scheduled to take. The sprints associated with the board are listed at the top of the roadmap along with the months. To see the exact dates of an epic, hover over its schedule bar. Sprints that have both start and end dates, and are associated with the board will be listed at the top of the roadmap, along with the months.
