Benjamin Sarah Willis Hawkins and family in Culpeper County, Virginia

I am going to start where I left off yesterday looking for what happens to the three Hawkins men and siblings who are named in the will of William Hawkins in Richmond County c.1715 between the time when each come of age in Richmond County, Virginia until the time that they are found in the vicinity of Orange and Culpeper County.  Yesterday's blog proved that they were not on the south side of the Rapidan River in Orange County.  Yesterday's blog ended with the statement:

So the question is when and to where do these Hawkins men move when they leave Richmond County and why?  I just looked at my Hawkins/Bourne data base and found the following:  

1782, Benjamin Hawkins taxed for 403.6 acres of land in Culpeper County (list of James Jett & Lewis Yancey) 1785 Culpeper Co Land Tax records shows William Hawkins, James Hawkins, Moses Hawkins  all “of Benj. Hawkins” with 135, 134 and 134 acres respectively (=403 acres total).