Scenario 1 varies.
The earliest Naturalization Acts* state that the children of aliens naturalize upon the naturalization of their parents, whether born here or not. This has changed over time so that now under 8 U.S.C. § 1401 (a) "a person born in the United States, and subject to the jurisdiction thereof" is a "citizen at birth" due to a broadly construed "subject to the jurisdiction thereof".
The foregoing illustrates that naturalization statute controls the "any person born here" set as well as the "naturalized citizen" set.
There are two problems with this construction:
1) Obviates the necessity of the grandfather clause of Art. II, § 1
2) Art. II eligibility requirements would be subject to statute. Specifically, statutes made pursuant to Art. I, § 8 would modify Art. II, § 1, which is a violation of Art. V. Congress' power of naturalization does not extend to modifying Art. II, § 1 or any other part of the Constitution.
* The Naturalization Act of 1790 and The Naturalization Act of 1795 both specify that children of aliens naturalize upon the naturalization of the parents.
Naturalization Act of March 26, 1790, ch. 3, 1 Stat. 103 http://memory.loc.gov/cgi-bin/ampage?collId=llsl&fileName=001/llsl001.db&recNum=226
§1 "...And the children of persons so naturalized, dwelling within the United States, being under the age of twenty-one years at the time of such naturalization, shall also be considered as citizens of the United States."
Naturalization Act of January 29, 1795, ch. 20, 1 Stat. 414 http://memory.loc.gov/cgi-bin/ampage?collId=llsl&fileName=001/llsl001.db&recNum=537
§3 "And be it further enacted, That the children of persons duly naturalized, dwelling within the United States, and being under the age of twenty-one years at the time of such naturalization; and the children of citizens of the United States, born out of the limits and jurisdiction of the United States, shall be considered as citizens of the United States"
You have been shown "case law" and the understanding of the Penn. Supreme Court which both affirm that these Naturalization Acts mean that the children of aliens naturalize upon the naturalization of their parents whether the children are born here or not.
If they didn't have natural born citizenship already, by virtue of being born here.
Whenever a person was born in any of the states, whether his parents were citizens or not, that person was a natural born citizen.
Virginia, for example, made a law that all persons born on their soil were citizens. In other places, it was merely due to acceptance of the common law. It was THE WAY THINGS HAD ALWAYS BEEN DONE. And nobody saw any reason at all to change it.
And ALL of the early States of the United States generally adopted the common law in all areas in which it didn't conflict with their own statutes.
"The children of aliens, born in this state, are considered as natural born subjects, and have the same rights with the rest of the citizens.”
Zephaniah Swift, A System of the Laws of the State of Connecticut: In Six Books (1795)