I didn't draft the NC set so I don't know if the Fawn Dr point is specifically because of the former NC 98 routing.
The NC 231/64 ALT thing is part of an interesting history there.
In Sep 1978, US 64 was moved to the freeway and NC 98 was extended east along old US 64. The road between the two had been US 64 Conn and was not redesignated as anything.
In Nov 1978, NC 98 was truncated back to its original/current endpoint and the US 64 Conn road became US 64 Bus/NC 231. US 64 Business was extended to Nashville.
I have never found an NCDOT to change 64 Bus to 64 ALT but official maps showed the change in 1980.
I have elected to extend NC 231 and leave US 64 ALT the way it was for now, unless somebody can provide evidence NC actually officially removed it. It was signed into the digital camera era.