I had to reorganize a lot of my work items in a way that required items not to be what they were. Fortunately, there’s a mechanism to change work item type. Within the work item, click on the ellipsis to access a menu of options. Select “Change type …”
Select the item type you want – I record the reason I needed the new type for posterity – then click “OK”. Save the work item and re-open it.
The one thing I’ve noticed is that fields that don’t exist on an item type (e.g. “effort” on “feature” items) are still present on the new item type even when that field does not normally display (e.g. “effort” on “user story” items).
I had wanted to classify my ADO work items as “features” (i.e. something someone asked to be added to an application), “bugs” (i.e. some intended functionality that was not working as designed). Bugs have a story point field, but features do not appear to have their own story point field. They, instead, are a roll-up of the story points of their subordinate user stories. Which makes sense except that I’ve now got to have two work items for every feature. Rolling up larger requests into sprint-sized work units is how we use epics. So I’ve instead found myself with user stories tagged with “features” that fall into epics (or don’t in the case of a small feature request).