Back in November and December I was scouring through early Tennessee records, trying to find at least one qualifying document that would show my Jones line was in Tennessee prior to 31 December 1796. When I was Salt Lake City for RootsTech, a brief research visit to the Family History Library turned up such a document. The book Jefferson County, Tennessee, Court Minutes, 1792-1795, by James L. Douthat and Roberta Hatcher (Signal Mountain Press, 1985), Page 40, included an entry from 1 August 1796, showing Thomas Jones. A photo is below:
At a Court of Pleas and quarter sessions held for Jefferson County in Dandridge on Monday the first day of August A. D. 1796. Present: Garrett Fitchgerald, Samuel Jack, and William Lillard Esquires.
The Court appoint Thomas Jones Overseer of the road from Seehorn's ferry to Miller's Mill and until it intersects with the road to Dandridge.
John Sehorn was a Revolutionary War veteran from Virginia. His home was Sehorn's Ferry on the south side of the French Broad River (today near the bridge where US-40 crosses Douglas Lake, up the river to the west of Taylors Bend (see this Rootsweb post from 2001, http://archiver.rootsweb.ancestry.com/th/read/TN-UPPER-CUMBERLAND/2001-03/0983904238).
Dandridge is across the river from Sehorn's Ferry. I don't know the location of Miller's Mill, so there's more research to determine the length of the road that Thomas was appointed to oversee.
In any case, I think this counts for meeting First Families of Tennessee status for the Jones line. The next step is to submit the package to the East Tennessee Historical Society. I'm aiming to do that later this month, and will report back on the response I receive.