Earlier I wrote about the many relocations on the AT in Virginia. A guess would be that about 80% of the trail in Virginia and West Virginia has been relocated from the original blazing in the 1920s. Probably more.
In northern Virginia, the ATC alerted hikers of the reroute along Highway 601. Newer residents didn't want the dirty hikers trekking through their backyards and discouraged hikers.
Notice this photo from 1974. The neighbors didn't even want hikers on the public road.
And here is the USGS topo map (1970) of the area.
Read more about this trail conflict in the excellent (and free) book PATC History by Tom Johnson [August 2020.