This is listed under UNLICENSED PERSONS question and answer ATF site.
May a person who resides in one State and owns property in another State purchase a firearm in either State?
If a person maintains a home in 2 States and resides in both States for certain periods of the year, he or she may, during the period of time the person actually resides in a particular State, purchase a firearm in that State. However, simply owning property in another State does not alone qualify the person to purchase a firearm in that State.
Yep, which is exactly why I am asking. It goes a step further and gives an example of such a condition, including those people that are "residents" on the weekends and/or summers, which is my case. I am in Alabama as I type this, at my weekend home, and I even get a substantial break on my county taxes because this is my second home. Thanks for reposting what I stated in the opening query.