There was no intentional change on my part. The word subject and citizen seemed interchangeable to them. Maybe it was habit since they'd all been 'subjects' since birth.
Jeff posted a few examples HERE , but they are unsourced.
-----
I do try to find old works, not recently published rehashes filled with contemporary interpretations. The one I posted is pretty much the oldest I've found. So far anyway.
November 22, 1788
……andPhillip Theobald & John de Polerisky, upon taking the oath of allegiance to this Commonwealth before two Justices of the Peace, & paying to the Secretary the fee in such case required, shall be deemed adjuded and taken to be free Citizens of this Commonwealth, and entitled to all the liberties, priviledges and immunities of natural born Citizens.
Acts and Resolves of Acts and Resolves Passed by the General Court of Massachusetts
Page 39
-----
I've fixed the wordage in my files. Thanks for bringing that to my attention, BTW.
In fact, the Acts and Resolves of Massachusetts shows that they used "natural born citizen" and "natural born subject" interchangeably.
Even President Washington was not immune to using the term subject.
In a letter to the Catholic clergy in the U.S., President Washington ended with,
"And may the members of your society in America, animated alone by the pure spirit of Christianity, and still conducting themselves as the faithful subjects of our free government, enjoy every temporal and spiritual felicity."
http://www.beliefnet.com/resourcelib/docs/97/Letter_from_George_Washington_to_the_Roman_Catholics_in_the_U_1.html