The simple reason may be that paper work was not the Continental Army's forte till later in the war.
Robert K. Wright, Jr., in "The Continental Army" (Center of Military History, 1983) is clear that the Continentals became a professional force after the 1778 reorganization. See Chapter 6. He states in a picture caption regarding enlistment forms (p.144), "By the second half of the Revolution, the Army's paperwork attained a high degree of sophistication."
This is an excellent treatment of the Army of the period and is available for sale or maybe in your local public library.
Included are many references to the 7th Virginia.
James B. Ronan II
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