Unlike the Conciliars, we don't believe that the Conciliar Church has any "ecclesial reality", and nobody is a "member" of it in any sense akin to how we say Catholics are members and of Christ, a theological sense, but in the sense that you might be a member if some, oh, political party or a book club, a natural sense. It's nothing more than an organization in a natural sense. There are some who belong to the Conciliar Church only materially, just because they mistakenly believe it to be the Catholic Church, but are still members of the Church due to their Baptism and profession of the True Faith.