When a job has parts cut from different materials, such as a steel top assembly with an aluminum subcomponent, creating a work order from Nest Planning used to pull in every part of the job, whatever material it was cut from. Now, in the Jobs to Nest panel, tick the parts you want and click the new WO Creation Rule button next to Create Nest. The work order gets only those parts, and the rest of the job stays in Nest Planning, ready to nest on its own material.
You need the Edit Job permission to see the button.