Need to change Subscriber / Call Transfer/ Transfer incoming calls to a phone/ to Yes, ring extension for.
Do you know the comparable setting in Unity Bulk Edit ?
After selecting the subscribers to update using the bulk edit tool:
1) Click on the transfer tab
2) Select the appropriate tab that you would like to update (standard, closed or alternate)
3) Set "Ring Phone" to True
4) Set "Set transfer number to be subscribers extension" checkbox as checked
Click next and then finally click update subscribers tab.
Always try this on a test user or two before applying in bulk to verify it is what you want.