A lot of people are annoyed because they think that Nine is now Ten, Ten is now Eleven, Eleven is now Twelve, etc….
because of John Hurt.
But, the Doctor says that he was “not acting under the name of the Doctor”
therefore, he’s not the “real” Ninth Doctor…
he can’t be any “Doctor” because he wasn’t acting under that name
personally I think he’s the Valeyard but that’s supposed to come in the future or something so I dunno you guys
but yeah: the way I see it, Nine is Nine and Ten is Ten and Eleven is Eleven…
and this new incarnation is something else entirely.
(they introduced him in the credit at the end as “the Doctor,” but I’m still interpreting this as him being another incarnation…but I don’t think it will officially through off the numbers.)