Iphone 6 update limit July 8, 2019 16 32 64 128 Iphone 6 ios update limit Iphone 6 plus update limit Iphone 6 plus ios update limit Iphone 6 software update limit Iphone 6 ios update limit ios 15 Iphone 6 plus software update limit Iphone 6 plus ios update limit ios 15 Iphone 6 update ios