Apple confirmed that iPhone 6s and iPhone 6s Plus units will be available at 8 a.m. local time Friday in Apple retail stores, but recommends getting there early to secure one. Apple notes that those living in tax-free U.S. states will have to make a reservation for their phone, as will residents of China, Hong Kong and Japan. Other U.S. customers can line up and take their chances Friday morning or make an online reservation for in-store pick up starting…