In CUCM admin, go to Call Routing > Call Pickup Group to see all pickup groups. To see where the call pickup groups are assigned, go to Bulk Administration > Phones > Generate Phone Reports. Search all phones and click Next. Give the report a name, add Description under Device Fields and Call Pickup Group under Line Fields. Click the radio button for Run Immediately and click Submit. Go to Bulk Administration > Job Scheduler to see the status of the job. When it is complete, click the job and open the CSV file.
Hope this helps.
Brandon