In this Catholic Herald comment/blog, William Oddie disagrees with the Anglican Professor John Milbank. The latter tries to say that Newman was a member of both the Church of England and the Catholic Church at the same time, which is an absurdity. As Dr. Oddie comments, Newman was a controversialist in these matters. After his conversion, he had little interest in Anglican matters. As I noted in my article published in Homiletic & Pastoral Review, he still valued the Church of England as the bulwark it was against atheism, but he thought it was only a temporary half-way house to the one True Church, the Catholic Church.
The late Father Stanley Jaki would agree with William Oddie. I have a copy of the Catholic Dossier issue dedicated to Cardinal Newman with Father Jaki's article on "Newman and His Converts: An Existential Ecclesiology."
Apropos of that, this would be a interesting mug to have in one's office.