When a structure is built using Speed mode, you can adjust the scope or hierarchy at any time by clicking the Modify structure button in the Structure toolbar.
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On the Modify Structure page, you can:
Add/remove projects
,or add project filters
Add, remove, or modify issue levels and group levels
Reorder issue and group levels
Filter or sort an issue or group level
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Once you've made your changes, click Apply and the .The structure will update automatically.