Backlog management is the process by which product management or a product owner (often in collaboration with others) continuously adds, adjusts, refines, and orders backlog items within the backlog to make sure the most valuable item is shipped to customers first. In a backlog, the item that is to be shipped first is on top and the ones that (supposed to) ship later are ordered more-or-less correctly towards the bottom.
The Portfolio Backlog is the highest-level backlog in SAFe. It provides a holding area for upcoming business and enabler Epics intended to create and evolve a comprehensive set of Solutions. © Scaled Agile, Inc.
By default its a list ordered by rank. In this solution the configuration is such that you can see the complete work hierarchy starting from Portfolio Epic to Capabilities, Features, User Stories and Bugs.
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