Product Backlog Refinement - doubt
Is this a timeboxed event? When this takes place, is the purpose of this is just to refine the ones selected for the current sprint or all the PBI's in general. Please clarify
Product Backlog refinement is not a Scrum event although in general each session can be timeboxed.
One timeboxed approach is to start at the top of the Product Backlog and work downwards. Once the timebox expires refinement will stop until the next session. In the next session refinement may be picked up again from the last item examined. After the final item has been considered, the process may recommence from the top of the Product Backlog.
A portion of a refinement session may be reserved for the further refinement of those high priority items which are likely candidates for planning in the next Sprint.