The more I search for Jagger family links, the more convinced I am that the descendants of Jeremiah, the 1630 emigre, did not remain entirely "American". It seems clear from the git-go that Jeremiah was not an adherent to the Protestant constraints. Other Jaggers, during Revolution, may have remained loyal to the crown and departed at least for a while.
John Jagger of Savannah did business on the "mosquito coast", probably in present day Belize. Possibly, even, Florida. Those areas traded hands and were subject to frequent conquest by Spanish. Belize, for a time, was governed from Jamaica I believe.
There is a Massachusetts marriage for John Jagger and Mary Tyhurst. Baptisms for four children: Lydia, John, Susanna and Ann. A later marriage for a Mary Tyhurst to a William Richardson. The son, John, it seems, is the one who married Sabella Burrington. That would make the John Jagger wills for NY and GA make sense.
The Georgia will mentions absolutely fascinating people and places. Sabella Burrington had been married to William Jones, had 4 children with him. One, Burrington Jones, may be the same for whom a town on Ambergris Cay, Belize, was named. Do a google search on the names :o)
In Georgia wills later than John J.'s, there is mention of an Elizabeth Burrington, sister of Thomas (an attorney in Savannah) in the will of Lachlan McGillivray, another absolutely fascinating guy - married a Creek Indian woman, had a son who became head Chief of the Creek nation - another larger than life person. Could spend your life studying just the issue of Creek, Choctaw and other indian lands.
Another possible link is Phineas Lyman, who commanded regiments in French/Indian war in which Jeremiah and Reuben served. Phineas obtained lands from England for settlement Adams Co. Mississippi, near Natchez. The first Jagger I have located in Miss. is Daniel, 1820, Wilkinson County. (next to Adams Co.)
If there is a link to the Elizabeth in Savannah and Sabella, I have not found it. Many came from Devon, England