Re: The Chinese variant of the XS will take two physical SIMs.
Bingo. Apple have only done this because it suits them. Either as something to assist negotiations with carriers or some other reason. They want to own everything. It's not unreasonable to anticipate them becoming an MVNO in certain regions. Imagine that, buy iPhone, fire it up, set up iTunes account, choose default Apple network, all your base are belong to us.