Planning source can be configured either for a particular project or all projects.
If needed, concurrency restrictions can be configured for a source. By default, concurrent events are allowed. User can configure a planning source in a way that concurrent events would not be allowed at all or concurrent events would not be allowed on assignee level. In addition, user can define issues as resources which will lead to concurrence blocking on issue level.
In addition, you can define what Jira issue fields you prefer to be displayed on the planning event and its information dialog. "e"- stands for the event block display, and "i" stands for the information dialog display.
For instance, you would like to set priority display on planning event block, and fixing version along with the original estimate to be displayed on information dialog of the planning.
In case you would like to save some time when creating numerous planning events, you might want to set Default Summary to "As source name" or "As issue summary".