Resume Carve now works for 3D designs. Available to Easel Pro subscribers, it works just like Resume Carve for non-3D designs.
To resume a carve that got interrupted, first select the "Resume Carve" option from the new dropdown option on the "Carve" button:

This will launch a carve walkthrough much like the one you're used to, except that there will be a new step to select the starting point for the carve right before you kick it off:

Warning: When starting a carve in the middle, it is important to exercise extra caution to make sure you are choosing a safe starting point.