The Phased-in approach to the bridge replacement was necessitated by USFWS refusal to grant new right of way required to relocate highway 12. NCDOT located deeds that allow NCDOT right aways as needed for the road into perpetuity thus allow NCDOT to revert to the original preference Road North/Bridge South.
The advantages/disadvantages and the savings associated with the Road North/Bridge South alternative are outlined in the following document.