Issue Summary

Company managed Project : 'Start Sprint' button goes missing when parallel sprint is disabled

Steps to Reproduce

1. Create a few JIRA tickets and then assign them to 3 sprints.
2. Start the 1st sprint.
3. Disable parallel sprint in JIRA Software Configuration
4. Go back to the backlog, the button will be missing.

Expected Results

The sprint result should be greyed out or throw some error

Actual Results

its disappears

The below exception is thrown in:

Workaround

1. Enable parallel sprints on https://<Instance>.atlassian.net/jira/settings/products/jira-software-configuration
2. Start the Sprint
3. Disable the parallel sprints on https://<Instance>.atlassian.net/jira/settings/products/jira-software-configuration