Rowan writes: "I understand that Bishop John-David Schofield has been accepted as a full member of the episcopal fellowship of the Province of the Southern Cone within the Anglican Communion and as such cannot be regarded as having withdrawn from the Anglican Communion. However, it is acknowledged that his exact status (especially given the complications surrounding the congregations associated with him) remains unclear on the basis of the general norms of Anglican Canon Law, and this constitutes one of the issues on which we hope for assistance from the Windsor Continuation Group. Bishop Schofield has elected to decline the invitation to the Lambeth Conference issued to him last year although that decision does not signal any withdrawal from the Communion. I hope there may be further careful reflection to clarify the terms on which he will exercise his ministry."
Hmm - sounds like there was a bit of behind the scenes going on regarding Schofield's status and he was allowed to "elect to decline" his invite.
Read more of who is there and who is not here