You all know that I have been searching since 1959 to find the extant Fly-records and to "place" the found-person in his/her rightful spot in one or another of ALL the known branches. The idea has been to try to know enough that a critical mass of data would help place the new ones found for placement.
The early ones are extremely difficult to document/prove relationship to another in the time-line. But we can speculate on the possibilities available in what we DO have.
I offer for consideration that Jamestown was founded in 1607; and John Fly had his passage paid by a landgrant that named him in 1635. I have detailed this in my "Chronology". In 1640 we see his putative son William is married to the widow Lymbree in Virginia. In 1662/1665 John Fly and two brothers are back in england, ready to return to the colonies. John, among them, goes to Virginia as an indentured servant. HIS son William gets involved in Bacon's Rebellion, sires ason, Jeremiah, and dies the year of Jeremiah's birth to Mary (Smith) Flye.
Jeremiah marries Mary, the Widow Bulls, and produces John and three girls. John, too, goes to England, where he marries Dorothy, siring John, William and Jeremiah returning to Virginia where Christina Fly was born in 1637 in Pensylvania. (Christina was baptised in 1637 in Douglassville, PA)